diff --git a/common/iobuf.c b/common/iobuf.c
index 822eabe1a..49e03da22 100644
--- a/common/iobuf.c
+++ b/common/iobuf.c
@@ -1,2829 +1,2913 @@
/* iobuf.c - File Handling for OpenPGP.
* Copyright (C) 1998, 1999, 2000, 2001, 2003, 2004, 2006, 2007, 2008,
* 2009, 2010, 2011 Free Software Foundation, Inc.
* Copyright (C) 2015 g10 Code GmbH
*
* This file is part of GnuPG.
*
* This file is free software; you can redistribute it and/or modify
* it under the terms of either
*
* - the GNU Lesser General Public License as published by the Free
* Software Foundation; either version 3 of the License, or (at
* your option) any later version.
*
* or
*
* - the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* or both in parallel, as here.
*
* This file is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see .
*/
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#ifdef HAVE_W32_SYSTEM
# ifdef HAVE_WINSOCK2_H
# include
# endif
# include
#endif
#ifdef __riscos__
# include
# include
#endif /* __riscos__ */
#include
#include "util.h"
#include "sysutils.h"
#include "iobuf.h"
/*-- Begin configurable part. --*/
/* The standard size of the internal buffers. */
#define DEFAULT_IOBUF_BUFFER_SIZE (64*1024)
/* To avoid a potential DoS with compression packets we better limit
the number of filters in a chain. */
#define MAX_NESTING_FILTER 64
+/* The threshold for switching to use external buffers directly
+ instead of the internal buffers. */
+#define IOBUF_ZEROCOPY_THRESHOLD_SIZE 1024
+
/*-- End configurable part. --*/
/* The size of the iobuffers. This can be changed using the
* iobuf_set_buffer_size function. */
static unsigned int iobuf_buffer_size = DEFAULT_IOBUF_BUFFER_SIZE;
#ifdef HAVE_W32_SYSTEM
# ifdef HAVE_W32CE_SYSTEM
# define FD_FOR_STDIN (es_fileno (es_stdin))
# define FD_FOR_STDOUT (es_fileno (es_stdout))
# else
# define FD_FOR_STDIN (GetStdHandle (STD_INPUT_HANDLE))
# define FD_FOR_STDOUT (GetStdHandle (STD_OUTPUT_HANDLE))
# endif
#else /*!HAVE_W32_SYSTEM*/
# define FD_FOR_STDIN (0)
# define FD_FOR_STDOUT (1)
#endif /*!HAVE_W32_SYSTEM*/
/* The context used by the file filter. */
typedef struct
{
gnupg_fd_t fp; /* Open file pointer or handle. */
int keep_open;
int no_cache;
int eof_seen;
int delayed_rc;
int print_only_name; /* Flags indicating that fname is not a real file. */
char fname[1]; /* Name of the file. */
} file_filter_ctx_t;
/* The context used by the estream filter. */
typedef struct
{
estream_t fp; /* Open estream handle. */
int keep_open;
int no_cache;
int eof_seen;
int use_readlimit; /* Take care of the readlimit. */
size_t readlimit; /* Number of bytes left to read. */
int print_only_name; /* Flags indicating that fname is not a real file. */
char fname[1]; /* Name of the file. */
} file_es_filter_ctx_t;
/* Object to control the "close cache". */
struct close_cache_s
{
struct close_cache_s *next;
gnupg_fd_t fp;
char fname[1];
};
typedef struct close_cache_s *close_cache_t;
static close_cache_t close_cache;
int iobuf_debug_mode;
#ifdef HAVE_W32_SYSTEM
typedef struct
{
int sock;
int keep_open;
int no_cache;
int eof_seen;
int print_only_name; /* Flag indicating that fname is not a real file. */
char fname[1]; /* Name of the file */
} sock_filter_ctx_t;
#endif /*HAVE_W32_SYSTEM*/
/* The first partial length header block must be of size 512 to make
* it easier (and more efficient) we use a min. block size of 512 for
* all chunks (but the last one) */
#define OP_MIN_PARTIAL_CHUNK 512
#define OP_MIN_PARTIAL_CHUNK_2POW 9
/* The context we use for the block filter (used to handle OpenPGP
length information header). */
typedef struct
{
int use;
size_t size;
size_t count;
int partial; /* 1 = partial header, 2 in last partial packet. */
char *buffer; /* Used for partial header. */
size_t buflen; /* Used size of buffer. */
int first_c; /* First character of a partial header (which is > 0). */
int eof;
}
block_filter_ctx_t;
/* Local prototypes. */
static int underflow (iobuf_t a, int clear_pending_eof);
static int underflow_target (iobuf_t a, int clear_pending_eof, size_t target);
static int translate_file_handle (int fd, int for_write);
/* Sends any pending data to the filter's FILTER function. Note: this
works on the filter and not on the whole pipeline. That is,
iobuf_flush doesn't necessarily cause data to be written to any
underlying file; it just causes any data buffered at the filter A
to be sent to A's filter function.
If A is a IOBUF_OUTPUT_TEMP filter, then this also enlarges the
buffer by iobuf_buffer_size.
May only be called on an IOBUF_OUTPUT or IOBUF_OUTPUT_TEMP filters. */
static int filter_flush (iobuf_t a);
/* This is a replacement for strcmp. Under W32 it does not
distinguish between backslash and slash. */
static int
fd_cache_strcmp (const char *a, const char *b)
{
#ifdef HAVE_DOSISH_SYSTEM
for (; *a && *b; a++, b++)
{
if (*a != *b && !((*a == '/' && *b == '\\')
|| (*a == '\\' && *b == '/')) )
break;
}
return *(const unsigned char *)a - *(const unsigned char *)b;
#else
return strcmp (a, b);
#endif
}
/*
* Invalidate (i.e. close) a cached iobuf
*/
static int
fd_cache_invalidate (const char *fname)
{
close_cache_t cc;
int rc = 0;
assert (fname);
if (DBG_IOBUF)
log_debug ("fd_cache_invalidate (%s)\n", fname);
for (cc = close_cache; cc; cc = cc->next)
{
if (cc->fp != GNUPG_INVALID_FD && !fd_cache_strcmp (cc->fname, fname))
{
if (DBG_IOBUF)
log_debug (" did (%s)\n", cc->fname);
#ifdef HAVE_W32_SYSTEM
if (!CloseHandle (cc->fp))
rc = -1;
#else
rc = close (cc->fp);
#endif
cc->fp = GNUPG_INVALID_FD;
}
}
return rc;
}
/* Try to sync changes to the disk. This is to avoid data loss during
a system crash in write/close/rename cycle on some file
systems. */
static int
fd_cache_synchronize (const char *fname)
{
int err = 0;
#ifdef HAVE_FSYNC
close_cache_t cc;
if (DBG_IOBUF)
log_debug ("fd_cache_synchronize (%s)\n", fname);
for (cc=close_cache; cc; cc = cc->next )
{
if (cc->fp != GNUPG_INVALID_FD && !fd_cache_strcmp (cc->fname, fname))
{
if (DBG_IOBUF)
log_debug (" did (%s)\n", cc->fname);
err = fsync (cc->fp);
}
}
#else
(void)fname;
#endif /*HAVE_FSYNC*/
return err;
}
static gnupg_fd_t
direct_open (const char *fname, const char *mode, int mode700)
{
#ifdef HAVE_W32_SYSTEM
unsigned long da, cd, sm;
HANDLE hfile;
(void)mode700;
/* Note, that we do not handle all mode combinations */
/* According to the ReactOS source it seems that open() of the
* standard MSW32 crt does open the file in shared mode which is
* something new for MS applications ;-)
*/
if (strchr (mode, '+'))
{
if (fd_cache_invalidate (fname))
return GNUPG_INVALID_FD;
da = GENERIC_READ | GENERIC_WRITE;
cd = OPEN_EXISTING;
sm = FILE_SHARE_READ | FILE_SHARE_WRITE;
}
else if (strchr (mode, 'w'))
{
if (fd_cache_invalidate (fname))
return GNUPG_INVALID_FD;
da = GENERIC_WRITE;
cd = CREATE_ALWAYS;
sm = FILE_SHARE_WRITE;
}
else
{
da = GENERIC_READ;
cd = OPEN_EXISTING;
sm = FILE_SHARE_READ;
}
/* We always use the Unicode version because it supports file names
* longer than MAX_PATH. (requires gpgrt 1.45) */
if (1)
{
wchar_t *wfname = gpgrt_fname_to_wchar (fname);
if (wfname)
{
hfile = CreateFileW (wfname, da, sm, NULL, cd,
FILE_ATTRIBUTE_NORMAL, NULL);
xfree (wfname);
}
else
hfile = INVALID_HANDLE_VALUE;
}
return hfile;
#else /*!HAVE_W32_SYSTEM*/
int oflag;
int cflag = S_IRUSR | S_IWUSR;
if (!mode700)
cflag |= S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
/* Note, that we do not handle all mode combinations */
if (strchr (mode, '+'))
{
if (fd_cache_invalidate (fname))
return GNUPG_INVALID_FD;
oflag = O_RDWR;
}
else if (strchr (mode, 'w'))
{
if (fd_cache_invalidate (fname))
return GNUPG_INVALID_FD;
oflag = O_WRONLY | O_CREAT | O_TRUNC;
}
else
{
oflag = O_RDONLY;
}
#ifdef O_BINARY
if (strchr (mode, 'b'))
oflag |= O_BINARY;
#endif
#ifdef __riscos__
{
struct stat buf;
/* Don't allow iobufs on directories */
if (!stat (fname, &buf) && S_ISDIR (buf.st_mode) && !S_ISREG (buf.st_mode))
return __set_errno (EISDIR);
}
#endif
return open (fname, oflag, cflag);
#endif /*!HAVE_W32_SYSTEM*/
}
/*
* Instead of closing an FD we keep it open and cache it for later reuse
* Note that this caching strategy only works if the process does not chdir.
*/
static void
fd_cache_close (const char *fname, gnupg_fd_t fp)
{
close_cache_t cc;
assert (fp);
if (!fname || !*fname)
{
#ifdef HAVE_W32_SYSTEM
CloseHandle (fp);
#else
close (fp);
#endif
if (DBG_IOBUF)
log_debug ("fd_cache_close (%d) real\n", (int)fp);
return;
}
/* try to reuse a slot */
for (cc = close_cache; cc; cc = cc->next)
{
if (cc->fp == GNUPG_INVALID_FD && !fd_cache_strcmp (cc->fname, fname))
{
cc->fp = fp;
if (DBG_IOBUF)
log_debug ("fd_cache_close (%s) used existing slot\n", fname);
return;
}
}
/* add a new one */
if (DBG_IOBUF)
log_debug ("fd_cache_close (%s) new slot created\n", fname);
cc = xcalloc (1, sizeof *cc + strlen (fname));
strcpy (cc->fname, fname);
cc->fp = fp;
cc->next = close_cache;
close_cache = cc;
}
/*
* Do a direct_open on FNAME but first try to reuse one from the fd_cache
*/
static gnupg_fd_t
fd_cache_open (const char *fname, const char *mode)
{
close_cache_t cc;
assert (fname);
for (cc = close_cache; cc; cc = cc->next)
{
if (cc->fp != GNUPG_INVALID_FD && !fd_cache_strcmp (cc->fname, fname))
{
gnupg_fd_t fp = cc->fp;
cc->fp = GNUPG_INVALID_FD;
if (DBG_IOBUF)
log_debug ("fd_cache_open (%s) using cached fp\n", fname);
#ifdef HAVE_W32_SYSTEM
if (SetFilePointer (fp, 0, NULL, FILE_BEGIN) == 0xffffffff)
{
log_error ("rewind file failed on handle %p: ec=%d\n",
fp, (int) GetLastError ());
fp = GNUPG_INVALID_FD;
}
#else
if (lseek (fp, 0, SEEK_SET) == (off_t) - 1)
{
log_error ("can't rewind fd %d: %s\n", fp, strerror (errno));
fp = GNUPG_INVALID_FD;
}
#endif
return fp;
}
}
if (DBG_IOBUF)
log_debug ("fd_cache_open (%s) not cached\n", fname);
return direct_open (fname, mode, 0);
}
static int
file_filter (void *opaque, int control, iobuf_t chain, byte * buf,
size_t * ret_len)
{
file_filter_ctx_t *a = opaque;
gnupg_fd_t f = a->fp;
size_t size = *ret_len;
size_t nbytes = 0;
int rc = 0;
(void)chain; /* Not used. */
if (control == IOBUFCTRL_UNDERFLOW)
{
log_assert (size); /* We need a buffer. */
if (a->eof_seen)
{
rc = -1;
*ret_len = 0;
}
else if (a->delayed_rc)
{
rc = a->delayed_rc;
a->delayed_rc = 0;
if (rc == -1)
a->eof_seen = -1;
*ret_len = 0;
}
else
{
#ifdef HAVE_W32_SYSTEM
unsigned long nread;
nbytes = 0;
if (!ReadFile (f, buf, size, &nread, NULL))
{
int ec = (int) GetLastError ();
if (ec != ERROR_BROKEN_PIPE)
{
rc = gpg_error_from_errno (ec);
log_error ("%s: read error: ec=%d\n", a->fname, ec);
}
}
else if (!nread)
{
a->eof_seen = 1;
rc = -1;
}
else
{
nbytes = nread;
}
#else
int n;
nbytes = 0;
read_more:
do
{
n = read (f, buf + nbytes, size - nbytes);
}
while (n == -1 && errno == EINTR);
if (n > 0)
{
nbytes += n;
if (nbytes < size)
goto read_more;
}
else if (!n) /* eof */
{
if (nbytes)
a->delayed_rc = -1;
else
{
a->eof_seen = 1;
rc = -1;
}
}
else /* error */
{
rc = gpg_error_from_syserror ();
if (gpg_err_code (rc) != GPG_ERR_EPIPE)
log_error ("%s: read error: %s\n", a->fname, gpg_strerror (rc));
if (nbytes)
{
a->delayed_rc = rc;
rc = 0;
}
}
#endif
*ret_len = nbytes;
}
}
else if (control == IOBUFCTRL_FLUSH)
{
if (size)
{
#ifdef HAVE_W32_SYSTEM
byte *p = buf;
unsigned long n;
nbytes = size;
do
{
if (size && !WriteFile (f, p, nbytes, &n, NULL))
{
int ec = (int) GetLastError ();
rc = gpg_error_from_errno (ec);
log_error ("%s: write error: ec=%d\n", a->fname, ec);
break;
}
p += n;
nbytes -= n;
}
while (nbytes);
nbytes = p - buf;
#else
byte *p = buf;
int n;
nbytes = size;
do
{
do
{
n = write (f, p, nbytes);
}
while (n == -1 && errno == EINTR);
if (n > 0)
{
p += n;
nbytes -= n;
}
}
while (n != -1 && nbytes);
if (n == -1)
{
rc = gpg_error_from_syserror ();
log_error ("%s: write error: %s\n", a->fname, strerror (errno));
}
nbytes = p - buf;
#endif
}
*ret_len = nbytes;
}
else if (control == IOBUFCTRL_INIT)
{
a->eof_seen = 0;
a->delayed_rc = 0;
a->keep_open = 0;
a->no_cache = 0;
}
else if (control == IOBUFCTRL_DESC)
{
mem2str (buf, "file_filter(fd)", *ret_len);
}
else if (control == IOBUFCTRL_FREE)
{
if (f != FD_FOR_STDIN && f != FD_FOR_STDOUT)
{
if (DBG_IOBUF)
log_debug ("%s: close fd/handle %d\n", a->fname, FD2INT (f));
if (!a->keep_open)
fd_cache_close (a->no_cache ? NULL : a->fname, f);
}
xfree (a); /* We can free our context now. */
}
return rc;
}
/* Similar to file_filter but using the estream system. */
static int
file_es_filter (void *opaque, int control, iobuf_t chain, byte * buf,
size_t * ret_len)
{
file_es_filter_ctx_t *a = opaque;
estream_t f = a->fp;
size_t size = *ret_len;
size_t nbytes = 0;
int rc = 0;
(void)chain; /* Not used. */
if (control == IOBUFCTRL_UNDERFLOW)
{
assert (size); /* We need a buffer. */
if (a->eof_seen)
{
rc = -1;
*ret_len = 0;
}
else if (a->use_readlimit)
{
nbytes = 0;
if (!a->readlimit)
{ /* eof */
a->eof_seen = 1;
rc = -1;
}
else
{
if (size > a->readlimit)
size = a->readlimit;
rc = es_read (f, buf, size, &nbytes);
if (rc == -1)
{ /* error */
rc = gpg_error_from_syserror ();
log_error ("%s: read error: %s\n", a->fname,strerror (errno));
}
else if (!nbytes)
{ /* eof */
a->eof_seen = 1;
rc = -1;
}
else
a->readlimit -= nbytes;
}
*ret_len = nbytes;
}
else
{
nbytes = 0;
rc = es_read (f, buf, size, &nbytes);
if (rc == -1)
{ /* error */
rc = gpg_error_from_syserror ();
log_error ("%s: read error: %s\n", a->fname, strerror (errno));
}
else if (!nbytes)
{ /* eof */
a->eof_seen = 1;
rc = -1;
}
*ret_len = nbytes;
}
}
else if (control == IOBUFCTRL_FLUSH)
{
if (size)
{
byte *p = buf;
size_t nwritten;
nbytes = size;
do
{
nwritten = 0;
if (es_write (f, p, nbytes, &nwritten))
{
rc = gpg_error_from_syserror ();
log_error ("%s: write error: %s\n",
a->fname, strerror (errno));
break;
}
p += nwritten;
nbytes -= nwritten;
}
while (nbytes);
nbytes = p - buf;
}
*ret_len = nbytes;
}
else if (control == IOBUFCTRL_INIT)
{
a->eof_seen = 0;
a->no_cache = 0;
}
else if (control == IOBUFCTRL_DESC)
{
mem2str (buf, "estream_filter", *ret_len);
}
else if (control == IOBUFCTRL_FREE)
{
if (f != es_stdin && f != es_stdout)
{
if (DBG_IOBUF)
log_debug ("%s: es_fclose %p\n", a->fname, f);
if (!a->keep_open)
es_fclose (f);
}
f = NULL;
xfree (a); /* We can free our context now. */
}
return rc;
}
#ifdef HAVE_W32_SYSTEM
/* Because network sockets are special objects under Lose32 we have to
use a dedicated filter for them. */
static int
sock_filter (void *opaque, int control, iobuf_t chain, byte * buf,
size_t * ret_len)
{
sock_filter_ctx_t *a = opaque;
size_t size = *ret_len;
size_t nbytes = 0;
int rc = 0;
(void)chain;
if (control == IOBUFCTRL_UNDERFLOW)
{
assert (size); /* need a buffer */
if (a->eof_seen)
{
rc = -1;
*ret_len = 0;
}
else
{
int nread;
nread = recv (a->sock, buf, size, 0);
if (nread == SOCKET_ERROR)
{
int ec = (int) WSAGetLastError ();
rc = gpg_error_from_errno (ec);
log_error ("socket read error: ec=%d\n", ec);
}
else if (!nread)
{
a->eof_seen = 1;
rc = -1;
}
else
{
nbytes = nread;
}
*ret_len = nbytes;
}
}
else if (control == IOBUFCTRL_FLUSH)
{
if (size)
{
byte *p = buf;
int n;
nbytes = size;
do
{
n = send (a->sock, p, nbytes, 0);
if (n == SOCKET_ERROR)
{
int ec = (int) WSAGetLastError ();
rc = gpg_error_from_errno (ec);
log_error ("socket write error: ec=%d\n", ec);
break;
}
p += n;
nbytes -= n;
}
while (nbytes);
nbytes = p - buf;
}
*ret_len = nbytes;
}
else if (control == IOBUFCTRL_INIT)
{
a->eof_seen = 0;
a->keep_open = 0;
a->no_cache = 0;
}
else if (control == IOBUFCTRL_DESC)
{
mem2str (buf, "sock_filter", *ret_len);
}
else if (control == IOBUFCTRL_FREE)
{
if (!a->keep_open)
closesocket (a->sock);
xfree (a); /* we can free our context now */
}
return rc;
}
#endif /*HAVE_W32_SYSTEM*/
/****************
* This is used to implement the block write mode.
* Block reading is done on a byte by byte basis in readbyte(),
* without a filter
*/
static int
block_filter (void *opaque, int control, iobuf_t chain, byte * buffer,
size_t * ret_len)
{
block_filter_ctx_t *a = opaque;
char *buf = (char *)buffer;
size_t size = *ret_len;
int c, needed, rc = 0;
char *p;
if (control == IOBUFCTRL_UNDERFLOW)
{
size_t n = 0;
p = buf;
assert (size); /* need a buffer */
if (a->eof) /* don't read any further */
rc = -1;
while (!rc && size)
{
if (!a->size)
{ /* get the length bytes */
if (a->partial == 2)
{
a->eof = 1;
if (!n)
rc = -1;
break;
}
else if (a->partial)
{
/* These OpenPGP introduced huffman like encoded length
* bytes are really a mess :-( */
if (a->first_c)
{
c = a->first_c;
a->first_c = 0;
}
else if ((c = iobuf_get (chain)) == -1)
{
log_error ("block_filter: 1st length byte missing\n");
rc = GPG_ERR_BAD_DATA;
break;
}
if (c < 192)
{
a->size = c;
a->partial = 2;
if (!a->size)
{
a->eof = 1;
if (!n)
rc = -1;
break;
}
}
else if (c < 224)
{
a->size = (c - 192) * 256;
if ((c = iobuf_get (chain)) == -1)
{
log_error
("block_filter: 2nd length byte missing\n");
rc = GPG_ERR_BAD_DATA;
break;
}
a->size += c + 192;
a->partial = 2;
if (!a->size)
{
a->eof = 1;
if (!n)
rc = -1;
break;
}
}
else if (c == 255)
{
size_t len = 0;
int i;
for (i = 0; i < 4; i++)
if ((c = iobuf_get (chain)) == -1)
break;
else
len = ((len << 8) | c);
if (i < 4)
{
log_error ("block_filter: invalid 4 byte length\n");
rc = GPG_ERR_BAD_DATA;
break;
}
a->size = len;
a->partial = 2;
if (!a->size)
{
a->eof = 1;
if (!n)
rc = -1;
break;
}
}
else
{ /* Next partial body length. */
a->size = 1 << (c & 0x1f);
}
/* log_debug("partial: ctx=%p c=%02x size=%u\n", a, c, a->size); */
}
else
BUG ();
}
while (!rc && size && a->size)
{
needed = size < a->size ? size : a->size;
c = iobuf_read (chain, p, needed);
if (c < needed)
{
if (c == -1)
c = 0;
log_error
("block_filter %p: read error (size=%lu,a->size=%lu)\n",
a, (ulong) size + c, (ulong) a->size + c);
rc = GPG_ERR_BAD_DATA;
}
else
{
size -= c;
a->size -= c;
p += c;
n += c;
}
}
}
*ret_len = n;
}
else if (control == IOBUFCTRL_FLUSH)
{
if (a->partial)
{ /* the complicated openpgp scheme */
size_t blen, n, nbytes = size + a->buflen;
assert (a->buflen <= OP_MIN_PARTIAL_CHUNK);
if (nbytes < OP_MIN_PARTIAL_CHUNK)
{
/* not enough to write a partial block out; so we store it */
if (!a->buffer)
a->buffer = xmalloc (OP_MIN_PARTIAL_CHUNK);
memcpy (a->buffer + a->buflen, buf, size);
a->buflen += size;
}
else
{ /* okay, we can write out something */
/* do this in a loop to use the most efficient block lengths */
p = buf;
do
{
/* find the best matching block length - this is limited
* by the size of the internal buffering */
for (blen = OP_MIN_PARTIAL_CHUNK * 2,
c = OP_MIN_PARTIAL_CHUNK_2POW + 1; blen <= nbytes;
blen *= 2, c++)
;
blen /= 2;
c--;
/* write the partial length header */
assert (c <= 0x1f); /*;-) */
c |= 0xe0;
iobuf_put (chain, c);
if ((n = a->buflen))
{ /* write stuff from the buffer */
assert (n == OP_MIN_PARTIAL_CHUNK);
if (iobuf_write (chain, a->buffer, n))
rc = gpg_error_from_syserror ();
a->buflen = 0;
nbytes -= n;
}
if ((n = nbytes) > blen)
n = blen;
if (n && iobuf_write (chain, p, n))
rc = gpg_error_from_syserror ();
p += n;
nbytes -= n;
}
while (!rc && nbytes >= OP_MIN_PARTIAL_CHUNK);
/* store the rest in the buffer */
if (!rc && nbytes)
{
assert (!a->buflen);
assert (nbytes < OP_MIN_PARTIAL_CHUNK);
if (!a->buffer)
a->buffer = xmalloc (OP_MIN_PARTIAL_CHUNK);
memcpy (a->buffer, p, nbytes);
a->buflen = nbytes;
}
}
}
else
BUG ();
}
else if (control == IOBUFCTRL_INIT)
{
if (DBG_IOBUF)
log_debug ("init block_filter %p\n", a);
if (a->partial)
a->count = 0;
else if (a->use == IOBUF_INPUT)
a->count = a->size = 0;
else
a->count = a->size; /* force first length bytes */
a->eof = 0;
a->buffer = NULL;
a->buflen = 0;
}
else if (control == IOBUFCTRL_DESC)
{
mem2str (buf, "block_filter", *ret_len);
}
else if (control == IOBUFCTRL_FREE)
{
if (a->use == IOBUF_OUTPUT)
{ /* write the end markers */
if (a->partial)
{
u32 len;
/* write out the remaining bytes without a partial header
* the length of this header may be 0 - but if it is
* the first block we are not allowed to use a partial header
* and frankly we can't do so, because this length must be
* a power of 2. This is _really_ complicated because we
* have to check the possible length of a packet prior
* to it's creation: a chain of filters becomes complicated
* and we need a lot of code to handle compressed packets etc.
* :-(((((((
*/
/* construct header */
len = a->buflen;
/*log_debug("partial: remaining length=%u\n", len ); */
if (len < 192)
rc = iobuf_put (chain, len);
else if (len < 8384)
{
if (!(rc = iobuf_put (chain, ((len - 192) / 256) + 192)))
rc = iobuf_put (chain, ((len - 192) % 256));
}
else
{ /* use a 4 byte header */
if (!(rc = iobuf_put (chain, 0xff)))
if (!(rc = iobuf_put (chain, (len >> 24) & 0xff)))
if (!(rc = iobuf_put (chain, (len >> 16) & 0xff)))
if (!(rc = iobuf_put (chain, (len >> 8) & 0xff)))
rc = iobuf_put (chain, len & 0xff);
}
if (!rc && len)
rc = iobuf_write (chain, a->buffer, len);
if (rc)
{
log_error ("block_filter: write error: %s\n",
strerror (errno));
rc = gpg_error_from_syserror ();
}
xfree (a->buffer);
a->buffer = NULL;
a->buflen = 0;
}
else
BUG ();
}
else if (a->size)
{
log_error ("block_filter: pending bytes!\n");
}
if (DBG_IOBUF)
log_debug ("free block_filter %p\n", a);
xfree (a); /* we can free our context now */
}
return rc;
}
/* Change the default size for all IOBUFs to KILOBYTE. This needs to
* be called before any iobufs are used and can only be used once.
* Returns the current value. Using 0 has no effect except for
* returning the current value. */
unsigned int
iobuf_set_buffer_size (unsigned int kilobyte)
{
static int used;
if (!used && kilobyte)
{
if (kilobyte < 4)
kilobyte = 4;
else if (kilobyte > 16*1024)
kilobyte = 16*1024;
iobuf_buffer_size = kilobyte * 1024;
used = 1;
}
return iobuf_buffer_size / 1024;
}
#define MAX_IOBUF_DESC 32
/*
* Fill the buffer by the description of iobuf A.
* The buffer size should be MAX_IOBUF_DESC (or larger).
* Returns BUF as (const char *).
*/
static const char *
iobuf_desc (iobuf_t a, byte *buf)
{
size_t len = MAX_IOBUF_DESC;
if (! a || ! a->filter)
memcpy (buf, "?", 2);
else
a->filter (a->filter_ov, IOBUFCTRL_DESC, NULL, buf, &len);
return buf;
}
static void
print_chain (iobuf_t a)
{
if (!DBG_IOBUF)
return;
for (; a; a = a->chain)
{
byte desc[MAX_IOBUF_DESC];
log_debug ("iobuf chain: %d.%d '%s' filter_eof=%d start=%d len=%d\n",
a->no, a->subno, iobuf_desc (a, desc), a->filter_eof,
(int) a->d.start, (int) a->d.len);
}
}
int
iobuf_print_chain (iobuf_t a)
{
print_chain (a);
return 0;
}
iobuf_t
iobuf_alloc (int use, size_t bufsize)
{
iobuf_t a;
static int number = 0;
assert (use == IOBUF_INPUT || use == IOBUF_INPUT_TEMP
|| use == IOBUF_OUTPUT || use == IOBUF_OUTPUT_TEMP);
if (bufsize == 0)
{
log_bug ("iobuf_alloc() passed a bufsize of 0!\n");
bufsize = iobuf_buffer_size;
}
a = xcalloc (1, sizeof *a);
a->use = use;
a->d.buf = xmalloc (bufsize);
a->d.size = bufsize;
+ a->e_d.buf = NULL;
+ a->e_d.len = 0;
+ a->e_d.used = 0;
+ a->e_d.preferred = 0;
a->no = ++number;
a->subno = 0;
a->real_fname = NULL;
return a;
}
int
iobuf_close (iobuf_t a)
{
iobuf_t a_chain;
size_t dummy_len = 0;
int rc = 0;
for (; a; a = a_chain)
{
byte desc[MAX_IOBUF_DESC];
int rc2 = 0;
a_chain = a->chain;
if (a->use == IOBUF_OUTPUT && (rc = filter_flush (a)))
log_error ("filter_flush failed on close: %s\n", gpg_strerror (rc));
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: close '%s'\n",
a->no, a->subno, iobuf_desc (a, desc));
if (a->filter && (rc2 = a->filter (a->filter_ov, IOBUFCTRL_FREE,
a->chain, NULL, &dummy_len)))
log_error ("IOBUFCTRL_FREE failed on close: %s\n", gpg_strerror (rc));
if (! rc && rc2)
/* Whoops! An error occurred. Save it in RC if we haven't
already recorded an error. */
rc = rc2;
xfree (a->real_fname);
if (a->d.buf)
{
memset (a->d.buf, 0, a->d.size); /* erase the buffer */
xfree (a->d.buf);
}
xfree (a);
}
return rc;
}
int
iobuf_cancel (iobuf_t a)
{
const char *s;
iobuf_t a2;
int rc;
#if defined(HAVE_W32_SYSTEM) || defined(__riscos__)
char *remove_name = NULL;
#endif
if (a && a->use == IOBUF_OUTPUT)
{
s = iobuf_get_real_fname (a);
if (s && *s)
{
#if defined(HAVE_W32_SYSTEM) || defined(__riscos__)
remove_name = xstrdup (s);
#else
remove (s);
#endif
}
}
/* send a cancel message to all filters */
for (a2 = a; a2; a2 = a2->chain)
{
size_t dummy = 0;
if (a2->filter)
a2->filter (a2->filter_ov, IOBUFCTRL_CANCEL, a2->chain, NULL, &dummy);
}
rc = iobuf_close (a);
#if defined(HAVE_W32_SYSTEM) || defined(__riscos__)
if (remove_name)
{
/* Argg, MSDOS does not allow removing open files. So
* we have to do it here */
#ifdef HAVE_W32CE_SYSTEM
wchar_t *wtmp = utf8_to_wchar (remove_name);
if (wtmp)
DeleteFile (wtmp);
xfree (wtmp);
#else
remove (remove_name);
#endif
xfree (remove_name);
}
#endif
return rc;
}
iobuf_t
iobuf_temp (void)
{
return iobuf_alloc (IOBUF_OUTPUT_TEMP, iobuf_buffer_size);
}
iobuf_t
iobuf_temp_with_content (const char *buffer, size_t length)
{
iobuf_t a;
int i;
a = iobuf_alloc (IOBUF_INPUT_TEMP, length);
assert (length == a->d.size);
/* memcpy (a->d.buf, buffer, length); */
for (i=0; i < length; i++)
a->d.buf[i] = buffer[i];
a->d.len = length;
return a;
}
int
iobuf_is_pipe_filename (const char *fname)
{
if (!fname || (*fname=='-' && !fname[1]) )
return 1;
return check_special_filename (fname, 0, 1) != -1;
}
static iobuf_t
do_open (const char *fname, int special_filenames,
int use, const char *opentype, int mode700)
{
iobuf_t a;
gnupg_fd_t fp;
file_filter_ctx_t *fcx;
size_t len = 0;
int print_only = 0;
int fd;
byte desc[MAX_IOBUF_DESC];
assert (use == IOBUF_INPUT || use == IOBUF_OUTPUT);
if (special_filenames
/* NULL or '-'. */
&& (!fname || (*fname == '-' && !fname[1])))
{
if (use == IOBUF_INPUT)
{
fp = FD_FOR_STDIN;
fname = "[stdin]";
}
else
{
fp = FD_FOR_STDOUT;
fname = "[stdout]";
}
print_only = 1;
}
else if (!fname)
return NULL;
else if (special_filenames
&& (fd = check_special_filename (fname, 0, 1)) != -1)
return iobuf_fdopen (translate_file_handle (fd, use == IOBUF_INPUT ? 0 : 1),
opentype);
else
{
if (use == IOBUF_INPUT)
fp = fd_cache_open (fname, opentype);
else
fp = direct_open (fname, opentype, mode700);
if (fp == GNUPG_INVALID_FD)
return NULL;
}
a = iobuf_alloc (use, iobuf_buffer_size);
fcx = xmalloc (sizeof *fcx + strlen (fname));
fcx->fp = fp;
fcx->print_only_name = print_only;
strcpy (fcx->fname, fname);
if (!print_only)
a->real_fname = xstrdup (fname);
a->filter = file_filter;
a->filter_ov = fcx;
file_filter (fcx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: open '%s' desc=%s fd=%d\n",
a->no, a->subno, fname, iobuf_desc (a, desc), FD2INT (fcx->fp));
return a;
}
iobuf_t
iobuf_open (const char *fname)
{
return do_open (fname, 1, IOBUF_INPUT, "rb", 0);
}
iobuf_t
iobuf_create (const char *fname, int mode700)
{
return do_open (fname, 1, IOBUF_OUTPUT, "wb", mode700);
}
iobuf_t
iobuf_openrw (const char *fname)
{
return do_open (fname, 0, IOBUF_OUTPUT, "r+b", 0);
}
static iobuf_t
do_iobuf_fdopen (int fd, const char *mode, int keep_open)
{
iobuf_t a;
gnupg_fd_t fp;
file_filter_ctx_t *fcx;
size_t len = 0;
fp = INT2FD (fd);
a = iobuf_alloc (strchr (mode, 'w') ? IOBUF_OUTPUT : IOBUF_INPUT,
iobuf_buffer_size);
fcx = xmalloc (sizeof *fcx + 20);
fcx->fp = fp;
fcx->print_only_name = 1;
fcx->keep_open = keep_open;
sprintf (fcx->fname, "[fd %d]", fd);
a->filter = file_filter;
a->filter_ov = fcx;
file_filter (fcx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: fdopen%s '%s'\n",
a->no, a->subno, keep_open? "_nc":"", fcx->fname);
iobuf_ioctl (a, IOBUF_IOCTL_NO_CACHE, 1, NULL);
return a;
}
iobuf_t
iobuf_fdopen (int fd, const char *mode)
{
return do_iobuf_fdopen (fd, mode, 0);
}
iobuf_t
iobuf_fdopen_nc (int fd, const char *mode)
{
return do_iobuf_fdopen (fd, mode, 1);
}
iobuf_t
iobuf_esopen (estream_t estream, const char *mode, int keep_open,
size_t readlimit)
{
iobuf_t a;
file_es_filter_ctx_t *fcx;
size_t len = 0;
a = iobuf_alloc (strchr (mode, 'w') ? IOBUF_OUTPUT : IOBUF_INPUT,
iobuf_buffer_size);
fcx = xtrymalloc (sizeof *fcx + 30);
fcx->fp = estream;
fcx->print_only_name = 1;
fcx->keep_open = keep_open;
fcx->readlimit = readlimit;
fcx->use_readlimit = !!readlimit;
snprintf (fcx->fname, 30, "[fd %p]", estream);
a->filter = file_es_filter;
a->filter_ov = fcx;
file_es_filter (fcx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: esopen%s '%s'\n",
a->no, a->subno, keep_open? "_nc":"", fcx->fname);
return a;
}
iobuf_t
iobuf_sockopen (int fd, const char *mode)
{
iobuf_t a;
#ifdef HAVE_W32_SYSTEM
sock_filter_ctx_t *scx;
size_t len;
a = iobuf_alloc (strchr (mode, 'w') ? IOBUF_OUTPUT : IOBUF_INPUT,
iobuf_buffer_size);
scx = xmalloc (sizeof *scx + 25);
scx->sock = fd;
scx->print_only_name = 1;
sprintf (scx->fname, "[sock %d]", fd);
a->filter = sock_filter;
a->filter_ov = scx;
sock_filter (scx, IOBUFCTRL_INIT, NULL, NULL, &len);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: sockopen '%s'\n", a->no, a->subno, scx->fname);
iobuf_ioctl (a, IOBUF_IOCTL_NO_CACHE, 1, NULL);
#else
a = iobuf_fdopen (fd, mode);
#endif
return a;
}
int
iobuf_ioctl (iobuf_t a, iobuf_ioctl_t cmd, int intval, void *ptrval)
{
byte desc[MAX_IOBUF_DESC];
if (cmd == IOBUF_IOCTL_KEEP_OPEN)
{
/* Keep system filepointer/descriptor open. This was used in
the past by http.c; this ioctl is not directly used
anymore. */
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: ioctl '%s' keep_open=%d\n",
a ? a->no : -1, a ? a->subno : -1, iobuf_desc (a, desc),
intval);
for (; a; a = a->chain)
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
b->keep_open = intval;
return 0;
}
#ifdef HAVE_W32_SYSTEM
else if (!a->chain && a->filter == sock_filter)
{
sock_filter_ctx_t *b = a->filter_ov;
b->keep_open = intval;
return 0;
}
#endif
}
else if (cmd == IOBUF_IOCTL_INVALIDATE_CACHE)
{
if (DBG_IOBUF)
log_debug ("iobuf-*.*: ioctl '%s' invalidate\n",
ptrval ? (char *) ptrval : "?");
if (!a && !intval && ptrval)
{
if (fd_cache_invalidate (ptrval))
return -1;
return 0;
}
}
else if (cmd == IOBUF_IOCTL_NO_CACHE)
{
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: ioctl '%s' no_cache=%d\n",
a ? a->no : -1, a ? a->subno : -1, iobuf_desc (a, desc),
intval);
for (; a; a = a->chain)
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
b->no_cache = intval;
return 0;
}
#ifdef HAVE_W32_SYSTEM
else if (!a->chain && a->filter == sock_filter)
{
sock_filter_ctx_t *b = a->filter_ov;
b->no_cache = intval;
return 0;
}
#endif
}
else if (cmd == IOBUF_IOCTL_FSYNC)
{
/* Do a fsync on the open fd and return any errors to the caller
of iobuf_ioctl. Note that we work on a file name here. */
if (DBG_IOBUF)
log_debug ("iobuf-*.*: ioctl '%s' fsync\n",
ptrval? (const char*)ptrval:"");
if (!a && !intval && ptrval)
{
return fd_cache_synchronize (ptrval);
}
}
return -1;
}
/****************
* Register an i/o filter.
*/
int
iobuf_push_filter (iobuf_t a,
int (*f) (void *opaque, int control,
iobuf_t chain, byte * buf, size_t * len),
void *ov)
{
return iobuf_push_filter2 (a, f, ov, 0);
}
int
iobuf_push_filter2 (iobuf_t a,
int (*f) (void *opaque, int control,
iobuf_t chain, byte * buf, size_t * len),
void *ov, int rel_ov)
{
iobuf_t b;
size_t dummy_len = 0;
int rc = 0;
if (a->use == IOBUF_OUTPUT && (rc = filter_flush (a)))
return rc;
if (a->subno >= MAX_NESTING_FILTER)
{
log_error ("i/o filter too deeply nested - corrupted data?\n");
return GPG_ERR_BAD_DATA;
}
/* We want to create a new filter and put it in front of A. A
simple implementation would do:
b = iobuf_alloc (...);
b->chain = a;
return a;
This is a bit problematic: A is the head of the pipeline and
there are potentially many pointers to it. Requiring the caller
to update all of these pointers is a burden.
An alternative implementation would add a level of indirection.
For instance, we could use a pipeline object, which contains a
pointer to the first filter in the pipeline. This is not what we
do either.
Instead, we allocate a new buffer (B) and copy the first filter's
state into that and use the initial buffer (A) for the new
filter. One limitation of this approach is that it is not
practical to maintain a pointer to a specific filter's state.
Before:
A
|
v 0x100 0x200
+----------+ +----------+
| filter x |--------->| filter y |---->....
+----------+ +----------+
After: B
|
v 0x300
+----------+
A | filter x |
| +----------+
v 0x100 ^ v 0x200
+----------+ +----------+
| filter w | | filter y |---->....
+----------+ +----------+
Note: filter x's address changed from 0x100 to 0x300, but A still
points to the head of the pipeline.
*/
b = xmalloc (sizeof *b);
memcpy (b, a, sizeof *b);
/* fixme: it is stupid to keep a copy of the name at every level
* but we need the name somewhere because the name known by file_filter
* may have been released when we need the name of the file */
b->real_fname = a->real_fname ? xstrdup (a->real_fname) : NULL;
/* remove the filter stuff from the new stream */
a->filter = NULL;
a->filter_ov = NULL;
a->filter_ov_owner = 0;
a->filter_eof = 0;
if (a->use == IOBUF_OUTPUT_TEMP)
/* A TEMP filter buffers any data sent to it; it does not forward
any data down the pipeline. If we add a new filter to the
pipeline, it shouldn't also buffer data. It should send it
downstream to be buffered. Thus, the correct type for a filter
added in front of an IOBUF_OUTPUT_TEMP filter is IOBUF_OUPUT, not
IOBUF_OUTPUT_TEMP. */
{
a->use = IOBUF_OUTPUT;
/* When pipeline is written to, the temp buffer's size is
increased accordingly. We don't need to allocate a 10 MB
buffer for a non-terminal filter. Just use the default
size. */
a->d.size = iobuf_buffer_size;
}
else if (a->use == IOBUF_INPUT_TEMP)
/* Same idea as above. */
{
a->use = IOBUF_INPUT;
a->d.size = iobuf_buffer_size;
}
/* The new filter (A) gets a new buffer.
If the pipeline is an output or temp pipeline, then giving the
buffer to the new filter means that data that was written before
the filter was pushed gets sent to the filter. That's clearly
wrong.
If the pipeline is an input pipeline, then giving the buffer to
the new filter (A) means that data that has read from (B), but
not yet read from the pipeline won't be processed by the new
filter (A)! That's certainly not what we want. */
a->d.buf = xmalloc (a->d.size);
a->d.len = 0;
a->d.start = 0;
/* disable nlimit for the new stream */
a->ntotal = b->ntotal + b->nbytes;
a->nlimit = a->nbytes = 0;
a->nofast = 0;
/* make a link from the new stream to the original stream */
a->chain = b;
/* setup the function on the new stream */
a->filter = f;
a->filter_ov = ov;
a->filter_ov_owner = rel_ov;
a->subno = b->subno + 1;
if (DBG_IOBUF)
{
byte desc[MAX_IOBUF_DESC];
log_debug ("iobuf-%d.%d: push '%s'\n",
a->no, a->subno, iobuf_desc (a, desc));
print_chain (a);
}
/* now we can initialize the new function if we have one */
if (a->filter && (rc = a->filter (a->filter_ov, IOBUFCTRL_INIT, a->chain,
NULL, &dummy_len)))
log_error ("IOBUFCTRL_INIT failed: %s\n", gpg_strerror (rc));
return rc;
}
/****************
* Remove an i/o filter.
*/
int
iobuf_pop_filter (iobuf_t a, int (*f) (void *opaque, int control,
iobuf_t chain, byte * buf, size_t * len),
void *ov)
{
iobuf_t b;
size_t dummy_len = 0;
int rc = 0;
byte desc[MAX_IOBUF_DESC];
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: pop '%s'\n",
a->no, a->subno, iobuf_desc (a, desc));
if (a->use == IOBUF_INPUT_TEMP || a->use == IOBUF_OUTPUT_TEMP)
{
/* This should be the last filter in the pipeline. */
assert (! a->chain);
return 0;
}
if (!a->filter)
{ /* this is simple */
b = a->chain;
assert (b);
xfree (a->d.buf);
xfree (a->real_fname);
memcpy (a, b, sizeof *a);
xfree (b);
return 0;
}
for (b = a; b; b = b->chain)
if (b->filter == f && (!ov || b->filter_ov == ov))
break;
if (!b)
log_bug ("iobuf_pop_filter(): filter function not found\n");
/* flush this stream if it is an output stream */
if (a->use == IOBUF_OUTPUT && (rc = filter_flush (b)))
{
log_error ("filter_flush failed in iobuf_pop_filter: %s\n",
gpg_strerror (rc));
return rc;
}
/* and tell the filter to free it self */
if (b->filter && (rc = b->filter (b->filter_ov, IOBUFCTRL_FREE, b->chain,
NULL, &dummy_len)))
{
log_error ("IOBUFCTRL_FREE failed: %s\n", gpg_strerror (rc));
return rc;
}
if (b->filter_ov && b->filter_ov_owner)
{
xfree (b->filter_ov);
b->filter_ov = NULL;
}
/* and see how to remove it */
if (a == b && !b->chain)
log_bug ("can't remove the last filter from the chain\n");
else if (a == b)
{ /* remove the first iobuf from the chain */
/* everything from b is copied to a. This is save because
* a flush has been done on the to be removed entry
*/
b = a->chain;
xfree (a->d.buf);
xfree (a->real_fname);
memcpy (a, b, sizeof *a);
xfree (b);
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: popped filter\n", a->no, a->subno);
}
else if (!b->chain)
{ /* remove the last iobuf from the chain */
log_bug ("Ohh jeee, trying to remove a head filter\n");
}
else
{ /* remove an intermediate iobuf from the chain */
log_bug ("Ohh jeee, trying to remove an intermediate filter\n");
}
return rc;
}
/****************
* read underflow: read at least one byte into the buffer and return
* the first byte or -1 on EOF.
*/
static int
underflow (iobuf_t a, int clear_pending_eof)
{
return underflow_target (a, clear_pending_eof, 1);
}
/****************
* read underflow: read TARGET bytes into the buffer and return
* the first byte or -1 on EOF.
*/
static int
underflow_target (iobuf_t a, int clear_pending_eof, size_t target)
{
size_t len;
int rc;
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: underflow: buffer size: %d; still buffered: %d => space for %d bytes\n",
a->no, a->subno,
(int) a->d.size, (int) (a->d.len - a->d.start),
(int) (a->d.size - (a->d.len - a->d.start)));
if (a->use == IOBUF_INPUT_TEMP)
/* By definition, there isn't more data to read into the
buffer. */
return -1;
assert (a->use == IOBUF_INPUT);
+ a->e_d.used = 0;
+
/* If there is still some buffered data, then move it to the start
of the buffer and try to fill the end of the buffer. (This is
useful if we are called from iobuf_peek().) */
assert (a->d.start <= a->d.len);
a->d.len -= a->d.start;
- memmove (a->d.buf, &a->d.buf[a->d.start], a->d.len);
+ if (a->d.len)
+ memmove (a->d.buf, &a->d.buf[a->d.start], a->d.len);
a->d.start = 0;
if (a->d.len < target && a->filter_eof)
/* The last time we tried to read from this filter, we got an EOF.
We couldn't return the EOF, because there was buffered data.
Since there is no longer any buffered data, return the
error. */
{
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: underflow: eof (pending eof)\n",
a->no, a->subno);
if (! clear_pending_eof)
return -1;
if (a->chain)
/* A filter follows this one. Free this filter. */
{
iobuf_t b = a->chain;
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: filter popped (pending EOF returned)\n",
a->no, a->subno);
xfree (a->d.buf);
xfree (a->real_fname);
memcpy (a, b, sizeof *a);
xfree (b);
print_chain (a);
}
else
a->filter_eof = 0; /* for the top level filter */
return -1; /* return one(!) EOF */
}
if (a->d.len == 0 && a->error)
/* The last time we tried to read from this filter, we got an
error. We couldn't return the error, because there was
buffered data. Since there is no longer any buffered data,
return the error. */
{
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: pending error (%s) returned\n",
a->no, a->subno, gpg_strerror (a->error));
return -1;
}
if (a->filter && ! a->filter_eof && ! a->error)
/* We have a filter function and the last time we tried to read we
didn't get an EOF or an error. Try to fill the buffer. */
{
/* Be careful to account for any buffered data. */
len = a->d.size - a->d.len;
- if (DBG_IOBUF)
- log_debug ("iobuf-%d.%d: underflow: A->FILTER (%lu bytes)\n",
- a->no, a->subno, (ulong) len);
+
+ if (a->e_d.preferred && a->d.len < IOBUF_ZEROCOPY_THRESHOLD_SIZE
+ && (IOBUF_ZEROCOPY_THRESHOLD_SIZE - a->d.len) < len)
+ {
+ if (DBG_IOBUF)
+ log_debug ("iobuf-%d.%d: limit buffering as external drain is "
+ "preferred\n", a->no, a->subno);
+ len = IOBUF_ZEROCOPY_THRESHOLD_SIZE - a->d.len;
+ }
+
if (len == 0)
/* There is no space for more data. Don't bother calling
A->FILTER. */
rc = 0;
else
- rc = a->filter (a->filter_ov, IOBUFCTRL_UNDERFLOW, a->chain,
- &a->d.buf[a->d.len], &len);
+ {
+ /* If no buffered data and drain buffer has been setup, and drain
+ * buffer is largish, read data directly to drain buffer. */
+ if (a->d.len == 0
+ && a->e_d.buf
+ && a->e_d.len >= IOBUF_ZEROCOPY_THRESHOLD_SIZE)
+ {
+ len = a->e_d.len;
+
+ if (DBG_IOBUF)
+ log_debug ("iobuf-%d.%d: underflow: A->FILTER (%lu bytes, to external drain)\n",
+ a->no, a->subno, (ulong)len);
+
+ rc = a->filter (a->filter_ov, IOBUFCTRL_UNDERFLOW, a->chain,
+ a->e_d.buf, &len);
+ a->e_d.used = len;
+ len = 0;
+ }
+ else
+ {
+ if (DBG_IOBUF)
+ log_debug ("iobuf-%d.%d: underflow: A->FILTER (%lu bytes)\n",
+ a->no, a->subno, (ulong)len);
+
+ rc = a->filter (a->filter_ov, IOBUFCTRL_UNDERFLOW, a->chain,
+ &a->d.buf[a->d.len], &len);
+ }
+ }
a->d.len += len;
if (DBG_IOBUF)
- log_debug ("iobuf-%d.%d: A->FILTER() returned rc=%d (%s), read %lu bytes\n",
+ log_debug ("iobuf-%d.%d: A->FILTER() returned rc=%d (%s), read %lu bytes%s\n",
a->no, a->subno,
rc, rc == 0 ? "ok" : rc == -1 ? "EOF" : gpg_strerror (rc),
- (ulong) len);
+ (ulong)(a->e_d.used ? a->e_d.used : len),
+ a->e_d.used ? " (to external buffer)" : "");
/* if( a->no == 1 ) */
/* log_hexdump (" data:", a->d.buf, len); */
if (rc == -1)
/* EOF. */
{
size_t dummy_len = 0;
/* Tell the filter to free itself */
if ((rc = a->filter (a->filter_ov, IOBUFCTRL_FREE, a->chain,
NULL, &dummy_len)))
log_error ("IOBUFCTRL_FREE failed: %s\n", gpg_strerror (rc));
/* Free everything except for the internal buffer. */
if (a->filter_ov && a->filter_ov_owner)
xfree (a->filter_ov);
a->filter_ov = NULL;
a->filter = NULL;
a->filter_eof = 1;
- if (clear_pending_eof && a->d.len == 0 && a->chain)
+ if (clear_pending_eof && a->d.len == 0 && a->e_d.used == 0
+ && a->chain)
/* We don't need to keep this filter around at all:
- we got an EOF
- we have no buffered data
- a filter follows this one.
Unlink this filter. */
{
iobuf_t b = a->chain;
if (DBG_IOBUF)
log_debug ("iobuf-%d.%d: pop in underflow (nothing buffered, got EOF)\n",
a->no, a->subno);
xfree (a->d.buf);
xfree (a->real_fname);
memcpy (a, b, sizeof *a);
xfree (b);
print_chain (a);
return -1;
}
- else if (a->d.len == 0)
+ else if (a->d.len == 0 && a->e_d.used == 0)
/* We can't unlink this filter (it is the only one in the
pipeline), but we can immediately return EOF. */
return -1;
}
else if (rc)
/* Record the error. */
{
a->error = rc;
- if (a->d.len == 0)
+ if (a->d.len == 0 && a->e_d.used == 0)
/* There is no buffered data. Immediately return EOF. */
return -1;
}
}
assert (a->d.start <= a->d.len);
+ if (a->e_d.used > 0)
+ return 0;
if (a->d.start < a->d.len)
return a->d.buf[a->d.start++];
/* EOF. */
return -1;
}
static int
filter_flush (iobuf_t a)
{
size_t len;
int rc;
if (a->use == IOBUF_OUTPUT_TEMP)
{ /* increase the temp buffer */
size_t newsize = a->d.size + iobuf_buffer_size;
if (DBG_IOBUF)
log_debug ("increasing temp iobuf from %lu to %lu\n",
(ulong) a->d.size, (ulong) newsize);
a->d.buf = xrealloc (a->d.buf, newsize);
a->d.size = newsize;
return 0;
}
else if (a->use != IOBUF_OUTPUT)
log_bug ("flush on non-output iobuf\n");
else if (!a->filter)
log_bug ("filter_flush: no filter\n");
len = a->d.len;
rc = a->filter (a->filter_ov, IOBUFCTRL_FLUSH, a->chain, a->d.buf, &len);
if (!rc && len != a->d.len)
{
log_info ("filter_flush did not write all!\n");
rc = GPG_ERR_INTERNAL;
}
else if (rc)
a->error = rc;
a->d.len = 0;
return rc;
}
int
iobuf_readbyte (iobuf_t a)
{
int c;
if (a->use == IOBUF_OUTPUT || a->use == IOBUF_OUTPUT_TEMP)
{
log_bug ("iobuf_readbyte called on a non-INPUT pipeline!\n");
return -1;
}
assert (a->d.start <= a->d.len);
if (a->nlimit && a->nbytes >= a->nlimit)
return -1; /* forced EOF */
if (a->d.start < a->d.len)
{
c = a->d.buf[a->d.start++];
}
else if ((c = underflow (a, 1)) == -1)
return -1; /* EOF */
assert (a->d.start <= a->d.len);
/* Note: if underflow doesn't return EOF, then it returns the first
byte that was read and advances a->d.start appropriately. */
a->nbytes++;
return c;
}
int
iobuf_read (iobuf_t a, void *buffer, unsigned int buflen)
{
unsigned char *buf = (unsigned char *)buffer;
int c, n;
if (a->use == IOBUF_OUTPUT || a->use == IOBUF_OUTPUT_TEMP)
{
log_bug ("iobuf_read called on a non-INPUT pipeline!\n");
return -1;
}
if (a->nlimit)
{
/* Handle special cases. */
for (n = 0; n < buflen; n++)
{
if ((c = iobuf_readbyte (a)) == -1)
{
if (!n)
return -1; /* eof */
break;
}
if (buf)
{
*buf = c;
buf++;
}
}
return n;
}
+ a->e_d.buf = NULL;
+ a->e_d.len = 0;
+
+ /* Hint for how full to fill iobuf internal drain buffer. */
+ a->e_d.preferred = (buf && buflen >= IOBUF_ZEROCOPY_THRESHOLD_SIZE);
+
n = 0;
do
{
if (n < buflen && a->d.start < a->d.len)
/* Drain the buffer. */
{
unsigned size = a->d.len - a->d.start;
if (size > buflen - n)
size = buflen - n;
if (buf)
memcpy (buf, a->d.buf + a->d.start, size);
n += size;
a->d.start += size;
if (buf)
buf += size;
}
if (n < buflen)
/* Draining the internal buffer didn't fill BUFFER. Call
underflow to read more data into the filter's internal
buffer. */
{
+ if (buf && n < buflen)
+ {
+ /* Setup external drain buffer for faster moving of data
+ * (avoid memcpy). */
+ a->e_d.buf = buf;
+ a->e_d.len = (buflen - n) / IOBUF_ZEROCOPY_THRESHOLD_SIZE
+ * IOBUF_ZEROCOPY_THRESHOLD_SIZE;
+ if (a->e_d.len == 0)
+ a->e_d.buf = NULL;
+ if (a->e_d.buf && DBG_IOBUF)
+ log_debug ("iobuf-%d.%d: reading to external buffer, %lu bytes\n",
+ a->no, a->subno, (ulong)a->e_d.len);
+ }
+
if ((c = underflow (a, 1)) == -1)
/* EOF. If we managed to read something, don't return EOF
now. */
{
+ a->e_d.buf = NULL;
+ a->e_d.len = 0;
a->nbytes += n;
return n ? n : -1 /*EOF*/;
}
- if (buf)
- *buf++ = c;
- n++;
+
+ if (a->e_d.buf && a->e_d.used > 0)
+ {
+ /* Drain buffer was used, 'c' only contains return code
+ * 0 or -1. */
+ n += a->e_d.used;
+ buf += a->e_d.used;
+ }
+ else
+ {
+ if (buf)
+ *buf++ = c;
+ n++;
+ }
+
+ a->e_d.buf = NULL;
+ a->e_d.len = 0;
}
}
while (n < buflen);
a->nbytes += n;
return n;
}
int
iobuf_peek (iobuf_t a, byte * buf, unsigned buflen)
{
int n = 0;
assert (buflen > 0);
assert (a->use == IOBUF_INPUT || a->use == IOBUF_INPUT_TEMP);
if (buflen > a->d.size)
/* We can't peek more than we can buffer. */
buflen = a->d.size;
/* Try to fill the internal buffer with enough data to satisfy the
request. */
while (buflen > a->d.len - a->d.start)
{
if (underflow_target (a, 0, buflen) == -1)
/* EOF. We can't read any more. */
break;
/* Underflow consumes the first character (it's the return
value). unget() it by resetting the "file position". */
assert (a->d.start == 1);
a->d.start = 0;
}
n = a->d.len - a->d.start;
if (n > buflen)
n = buflen;
if (n == 0)
/* EOF. */
return -1;
memcpy (buf, &a->d.buf[a->d.start], n);
return n;
}
int
iobuf_writebyte (iobuf_t a, unsigned int c)
{
int rc;
if (a->use == IOBUF_INPUT || a->use == IOBUF_INPUT_TEMP)
{
log_bug ("iobuf_writebyte called on an input pipeline!\n");
return -1;
}
if (a->d.len == a->d.size)
if ((rc=filter_flush (a)))
return rc;
assert (a->d.len < a->d.size);
a->d.buf[a->d.len++] = c;
return 0;
}
int
iobuf_write (iobuf_t a, const void *buffer, unsigned int buflen)
{
const unsigned char *buf = (const unsigned char *)buffer;
int rc;
if (a->use == IOBUF_INPUT || a->use == IOBUF_INPUT_TEMP)
{
log_bug ("iobuf_write called on an input pipeline!\n");
return -1;
}
do
{
if (buflen && a->d.len < a->d.size)
{
unsigned size = a->d.size - a->d.len;
if (size > buflen)
size = buflen;
memcpy (a->d.buf + a->d.len, buf, size);
buflen -= size;
buf += size;
a->d.len += size;
}
if (buflen)
{
rc = filter_flush (a);
if (rc)
return rc;
}
}
while (buflen);
return 0;
}
int
iobuf_writestr (iobuf_t a, const char *buf)
{
if (a->use == IOBUF_INPUT || a->use == IOBUF_INPUT_TEMP)
{
log_bug ("iobuf_writestr called on an input pipeline!\n");
return -1;
}
return iobuf_write (a, buf, strlen (buf));
}
int
iobuf_write_temp (iobuf_t dest, iobuf_t source)
{
assert (source->use == IOBUF_OUTPUT || source->use == IOBUF_OUTPUT_TEMP);
assert (dest->use == IOBUF_OUTPUT || dest->use == IOBUF_OUTPUT_TEMP);
iobuf_flush_temp (source);
return iobuf_write (dest, source->d.buf, source->d.len);
}
size_t
iobuf_temp_to_buffer (iobuf_t a, byte * buffer, size_t buflen)
{
byte desc[MAX_IOBUF_DESC];
size_t n;
while (1)
{
int rc = filter_flush (a);
if (rc)
log_bug ("Flushing iobuf %d.%d (%s) from iobuf_temp_to_buffer failed. Ignoring.\n",
a->no, a->subno, iobuf_desc (a, desc));
if (! a->chain)
break;
a = a->chain;
}
n = a->d.len;
if (n > buflen)
n = buflen;
memcpy (buffer, a->d.buf, n);
return n;
}
/* Copies the data from the input iobuf SOURCE to the output iobuf
DEST until either an error is encountered or EOF is reached.
Returns the number of bytes copies. */
size_t
iobuf_copy (iobuf_t dest, iobuf_t source)
{
char *temp;
size_t temp_size;
size_t nread;
size_t nwrote = 0;
size_t max_read = 0;
int err;
assert (source->use == IOBUF_INPUT || source->use == IOBUF_INPUT_TEMP);
assert (dest->use == IOBUF_OUTPUT || source->use == IOBUF_OUTPUT_TEMP);
if (iobuf_error (dest))
return -1;
/* Use iobuf buffer size for temporary buffer. */
temp_size = iobuf_set_buffer_size(0) * 1024;
temp = xmalloc (temp_size);
while (1)
{
nread = iobuf_read (source, temp, temp_size);
if (nread == -1)
/* EOF. */
break;
if (nread > max_read)
max_read = nread;
err = iobuf_write (dest, temp, nread);
if (err)
break;
nwrote += nread;
}
/* Burn the buffer. */
if (max_read)
wipememory (temp, max_read);
xfree (temp);
return nwrote;
}
void
iobuf_flush_temp (iobuf_t temp)
{
if (temp->use == IOBUF_INPUT || temp->use == IOBUF_INPUT_TEMP)
log_bug ("iobuf_flush_temp called on an input pipeline!\n");
while (temp->chain)
iobuf_pop_filter (temp, temp->filter, NULL);
}
void
iobuf_set_limit (iobuf_t a, off_t nlimit)
{
if (nlimit)
a->nofast = 1;
else
a->nofast = 0;
a->nlimit = nlimit;
a->ntotal += a->nbytes;
a->nbytes = 0;
}
off_t
iobuf_get_filelength (iobuf_t a, int *overflow)
{
if (overflow)
*overflow = 0;
/* Hmmm: file_filter may have already been removed */
for ( ; a->chain; a = a->chain )
;
if (a->filter != file_filter)
return 0;
{
file_filter_ctx_t *b = a->filter_ov;
gnupg_fd_t fp = b->fp;
#if defined(HAVE_W32_SYSTEM)
ulong size;
static int (* __stdcall get_file_size_ex) (void *handle,
LARGE_INTEGER *r_size);
static int get_file_size_ex_initialized;
if (!get_file_size_ex_initialized)
{
void *handle;
handle = dlopen ("kernel32.dll", RTLD_LAZY);
if (handle)
{
get_file_size_ex = dlsym (handle, "GetFileSizeEx");
if (!get_file_size_ex)
dlclose (handle);
}
get_file_size_ex_initialized = 1;
}
if (get_file_size_ex)
{
/* This is a newer system with GetFileSizeEx; we use this
then because it seem that GetFileSize won't return a
proper error in case a file is larger than 4GB. */
LARGE_INTEGER exsize;
if (get_file_size_ex (fp, &exsize))
{
if (!exsize.u.HighPart)
return exsize.u.LowPart;
if (overflow)
*overflow = 1;
return 0;
}
}
else
{
if ((size=GetFileSize (fp, NULL)) != 0xffffffff)
return size;
}
log_error ("GetFileSize for handle %p failed: %s\n",
fp, w32_strerror (-1));
#else /*!HAVE_W32_SYSTEM*/
{
struct stat st;
if ( !fstat (FD2INT (fp), &st) )
return st.st_size;
log_error("fstat() failed: %s\n", strerror(errno) );
}
#endif /*!HAVE_W32_SYSTEM*/
}
return 0;
}
int
iobuf_get_fd (iobuf_t a)
{
for (; a->chain; a = a->chain)
;
if (a->filter != file_filter)
return -1;
{
file_filter_ctx_t *b = a->filter_ov;
gnupg_fd_t fp = b->fp;
return FD2INT (fp);
}
}
off_t
iobuf_tell (iobuf_t a)
{
return a->ntotal + a->nbytes;
}
#if !defined(HAVE_FSEEKO) && !defined(fseeko)
#ifdef HAVE_LIMITS_H
# include
#endif
#ifndef LONG_MAX
# define LONG_MAX ((long) ((unsigned long) -1 >> 1))
#endif
#ifndef LONG_MIN
# define LONG_MIN (-1 - LONG_MAX)
#endif
/****************
* A substitute for fseeko, for hosts that don't have it.
*/
static int
fseeko (FILE * stream, off_t newpos, int whence)
{
while (newpos != (long) newpos)
{
long pos = newpos < 0 ? LONG_MIN : LONG_MAX;
if (fseek (stream, pos, whence) != 0)
return -1;
newpos -= pos;
whence = SEEK_CUR;
}
return fseek (stream, (long) newpos, whence);
}
#endif
int
iobuf_seek (iobuf_t a, off_t newpos)
{
file_filter_ctx_t *b = NULL;
if (a->use == IOBUF_OUTPUT || a->use == IOBUF_INPUT)
{
/* Find the last filter in the pipeline. */
for (; a->chain; a = a->chain)
;
if (a->filter != file_filter)
return -1;
b = a->filter_ov;
#ifdef HAVE_W32_SYSTEM
if (SetFilePointer (b->fp, newpos, NULL, FILE_BEGIN) == 0xffffffff)
{
log_error ("SetFilePointer failed on handle %p: ec=%d\n",
b->fp, (int) GetLastError ());
return -1;
}
#else
if (lseek (b->fp, newpos, SEEK_SET) == (off_t) - 1)
{
log_error ("can't lseek: %s\n", strerror (errno));
return -1;
}
#endif
/* Discard the buffer it is not a temp stream. */
a->d.len = 0;
}
a->d.start = 0;
a->nbytes = 0;
a->nlimit = 0;
a->nofast = 0;
a->ntotal = newpos;
a->error = 0;
/* It is impossible for A->CHAIN to be non-NULL. If A is an INPUT
or OUTPUT buffer, then we find the last filter, which is defined
as A->CHAIN being NULL. If A is a TEMP filter, then A must be
the only filter in the pipe: when iobuf_push_filter adds a filter
to the front of a pipeline, it sets the new filter to be an
OUTPUT filter if the pipeline is an OUTPUT or TEMP pipeline and
to be an INPUT filter if the pipeline is an INPUT pipeline.
Thus, only the last filter in a TEMP pipeline can be a */
/* remove filters, but the last */
if (a->chain)
log_debug ("iobuf_pop_filter called in iobuf_seek - please report\n");
while (a->chain)
iobuf_pop_filter (a, a->filter, NULL);
return 0;
}
const char *
iobuf_get_real_fname (iobuf_t a)
{
if (a->real_fname)
return a->real_fname;
/* the old solution */
for (; a; a = a->chain)
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
return b->print_only_name ? NULL : b->fname;
}
return NULL;
}
const char *
iobuf_get_fname (iobuf_t a)
{
for (; a; a = a->chain)
if (!a->chain && a->filter == file_filter)
{
file_filter_ctx_t *b = a->filter_ov;
return b->fname;
}
return NULL;
}
const char *
iobuf_get_fname_nonnull (iobuf_t a)
{
const char *fname;
fname = iobuf_get_fname (a);
return fname? fname : "[?]";
}
/****************
* Enable or disable partial body length mode (RFC 4880 4.2.2.4).
*
* If LEN is 0, this disables partial block mode by popping the
* partial body length filter, which must be the most recently
* added filter.
*
* If LEN is non-zero, it pushes a partial body length filter. If
* this is a read filter, LEN must be the length byte from the first
* chunk and A should be position just after this first partial body
* length header.
*/
void
iobuf_set_partial_body_length_mode (iobuf_t a, size_t len)
{
if (!len)
/* Disable partial body length mode. */
{
if (a->use == IOBUF_INPUT)
log_debug ("iobuf_pop_filter called in set_partial_block_mode"
" - please report\n");
log_assert (a->filter == block_filter);
iobuf_pop_filter (a, block_filter, NULL);
}
else
/* Enabled partial body length mode. */
{
block_filter_ctx_t *ctx = xcalloc (1, sizeof *ctx);
ctx->use = a->use;
ctx->partial = 1;
ctx->size = 0;
ctx->first_c = len;
iobuf_push_filter (a, block_filter, ctx);
}
}
unsigned int
iobuf_read_line (iobuf_t a, byte ** addr_of_buffer,
unsigned *length_of_buffer, unsigned *max_length)
{
int c;
char *buffer = (char *)*addr_of_buffer;
unsigned length = *length_of_buffer;
unsigned nbytes = 0;
unsigned maxlen = *max_length;
char *p;
/* The code assumes that we have space for at least a newline and a
NUL character in the buffer. This requires at least 2 bytes. We
don't complicate the code by handling the stupid corner case, but
simply assert that it can't happen. */
assert (!buffer || length >= 2 || maxlen >= 2);
if (!buffer || length <= 1)
/* must allocate a new buffer */
{
length = 256 <= maxlen ? 256 : maxlen;
buffer = xrealloc (buffer, length);
*addr_of_buffer = (unsigned char *)buffer;
*length_of_buffer = length;
}
p = buffer;
while (1)
{
if (!a->nofast && a->d.start < a->d.len && nbytes < length - 1)
/* Fast path for finding '\n' by using standard C library's optimized
memchr. */
{
unsigned size = a->d.len - a->d.start;
byte *newline_pos;
if (size > length - 1 - nbytes)
size = length - 1 - nbytes;
newline_pos = memchr (a->d.buf + a->d.start, '\n', size);
if (newline_pos)
{
/* Found newline, copy buffer and return. */
size = (newline_pos - (a->d.buf + a->d.start)) + 1;
memcpy (p, a->d.buf + a->d.start, size);
p += size;
nbytes += size;
a->d.start += size;
a->nbytes += size;
break;
}
else
{
/* No newline, copy buffer and continue. */
memcpy (p, a->d.buf + a->d.start, size);
p += size;
nbytes += size;
a->d.start += size;
a->nbytes += size;
}
}
else
{
c = iobuf_readbyte (a);
if (c == -1)
break;
*p++ = c;
nbytes++;
if (c == '\n')
break;
}
if (nbytes == length - 1)
/* We don't have enough space to add a \n and a \0. Increase
the buffer size. */
{
if (length == maxlen)
/* We reached the buffer's size limit! */
{
/* Skip the rest of the line. */
while ((c = iobuf_get (a)) != -1 && c != '\n')
;
/* p is pointing at the last byte in the buffer. We
always terminate the line with "\n\0" so overwrite
the previous byte with a \n. */
assert (p > buffer);
p[-1] = '\n';
/* Indicate truncation. */
*max_length = 0;
break;
}
length += length < 1024 ? 256 : 1024;
if (length > maxlen)
length = maxlen;
buffer = xrealloc (buffer, length);
*addr_of_buffer = (unsigned char *)buffer;
*length_of_buffer = length;
p = buffer + nbytes;
}
}
/* Add the terminating NUL. */
*p = 0;
/* Return the number of characters written to the buffer including
the newline, but not including the terminating NUL. */
return nbytes;
}
static int
translate_file_handle (int fd, int for_write)
{
#if defined(HAVE_W32CE_SYSTEM)
/* This is called only with one of the special filenames. Under
W32CE the FD here is not a file descriptor but a rendezvous id,
thus we need to finish the pipe first. */
fd = _assuan_w32ce_finish_pipe (fd, for_write);
#elif defined(HAVE_W32_SYSTEM)
{
int x;
(void)for_write;
if (fd == 0)
x = (int) GetStdHandle (STD_INPUT_HANDLE);
else if (fd == 1)
x = (int) GetStdHandle (STD_OUTPUT_HANDLE);
else if (fd == 2)
x = (int) GetStdHandle (STD_ERROR_HANDLE);
else
x = fd;
if (x == -1)
log_debug ("GetStdHandle(%d) failed: ec=%d\n",
fd, (int) GetLastError ());
fd = x;
}
#else
(void)for_write;
#endif
return fd;
}
void
iobuf_skip_rest (iobuf_t a, unsigned long n, int partial)
{
if ( partial )
{
for (;;)
{
if (a->nofast || a->d.start >= a->d.len)
{
if (iobuf_readbyte (a) == -1)
{
break;
}
}
else
{
unsigned long count = a->d.len - a->d.start;
a->nbytes += count;
a->d.start = a->d.len;
}
}
}
else
{
unsigned long remaining = n;
while (remaining > 0)
{
if (a->nofast || a->d.start >= a->d.len)
{
if (iobuf_readbyte (a) == -1)
{
break;
}
--remaining;
}
else
{
unsigned long count = a->d.len - a->d.start;
if (count > remaining)
{
count = remaining;
}
a->nbytes += count;
a->d.start += count;
remaining -= count;
}
}
}
}
diff --git a/common/iobuf.h b/common/iobuf.h
index a3d9bd547..f527fbf16 100644
--- a/common/iobuf.h
+++ b/common/iobuf.h
@@ -1,623 +1,643 @@
/* iobuf.h - I/O buffer
* Copyright (C) 1998, 1999, 2000, 2001, 2003,
* 2010 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* This file is free software; you can redistribute it and/or modify
* it under the terms of either
*
* - the GNU Lesser General Public License as published by the Free
* Software Foundation; either version 3 of the License, or (at
* your option) any later version.
*
* or
*
* - the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* or both in parallel, as here.
*
* This file is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see .
*/
#ifndef GNUPG_COMMON_IOBUF_H
#define GNUPG_COMMON_IOBUF_H
/* An iobuf is basically a filter in a pipeline.
Consider the following command, which consists of three filters
that are chained together:
$ cat file | base64 --decode | gunzip
The first filter reads the file from the file system and sends that
data to the second filter. The second filter decodes
base64-encoded data and sends the data to the third and last
filter. The last filter decompresses the data and the result is
displayed on the terminal. The iobuf system works in the same way
where each iobuf is a filter and the individual iobufs can be
chained together.
There are number of predefined filters. iobuf_open(), for
instance, creates a filter that reads from a specified file. And,
iobuf_temp_with_content() creates a filter that returns some
specified contents. There are also filters for writing content.
iobuf_openrw opens a file for writing. iobuf_temp creates a filter
that writes data to a fixed-sized buffer.
To chain filters together, you use the iobuf_push_filter()
function. The filters are chained together using the chain field
in the iobuf_t.
A pipeline can only be used for reading (IOBUF_INPUT) or for
writing (IOBUF_OUTPUT / IOBUF_OUTPUT_TEMP). When reading, data
flows from the last filter towards the first. That is, the user
calls iobuf_read(), the module reads from the first filter, which
gets its input from the second filter, etc. When writing, data
flows from the first filter towards the last. In this case, when
the user calls iobuf_write(), the data is written to the first
filter, which writes the transformed data to the second filter,
etc.
An iobuf_t contains some state about the filter. For instance, it
indicates if the filter has already returned EOF (filter_eof) and
the next filter in the pipeline, if any (chain). It also contains
a function pointer, filter. This is a generic function. It is
called when input is needed or output is available. In this case
it is passed a pointer to some filter-specific persistent state
(filter_ov), the actual operation, the next filter in the chain, if
any, and a buffer that either contains the contents to write, if
the pipeline is setup to write data, or is the place to store data,
if the pipeline is setup to read data.
Unlike a Unix pipeline, an IOBUF pipeline can return EOF multiple
times. This is similar to the following:
{ cat file1; cat file2; } | grep foo
However, instead of grep seeing a single stream, grep would see
each byte stream followed by an EOF marker. (When a filter returns
EOF, the EOF is returned to the user exactly once and then the
filter is removed from the pipeline.) */
/* For estream_t. */
#include
#include "../common/types.h"
#include "../common/sysutils.h"
#define DBG_IOBUF iobuf_debug_mode
/* Filter control modes. */
enum
{
IOBUFCTRL_INIT = 1,
IOBUFCTRL_FREE = 2,
IOBUFCTRL_UNDERFLOW = 3,
IOBUFCTRL_FLUSH = 4,
IOBUFCTRL_DESC = 5,
IOBUFCTRL_CANCEL = 6,
IOBUFCTRL_USER = 16
};
/* Command codes for iobuf_ioctl. */
typedef enum
{
IOBUF_IOCTL_KEEP_OPEN = 1, /* Uses intval. */
IOBUF_IOCTL_INVALIDATE_CACHE = 2, /* Uses ptrval. */
IOBUF_IOCTL_NO_CACHE = 3, /* Uses intval. */
IOBUF_IOCTL_FSYNC = 4 /* Uses ptrval. */
} iobuf_ioctl_t;
enum iobuf_use
{
/* Pipeline is in input mode. The data flows from the end to the
beginning. That is, when reading from the pipeline, the first
filter gets its input from the second filter, etc. */
IOBUF_INPUT,
/* Pipeline is in input mode. The last filter in the pipeline is
a temporary buffer from which the data is "read". */
IOBUF_INPUT_TEMP,
/* Pipeline is in output mode. The data flows from the beginning
to the end. That is, when writing to the pipeline, the user
writes to the first filter, which transforms the data and sends
it to the second filter, etc. */
IOBUF_OUTPUT,
/* Pipeline is in output mode. The last filter in the pipeline is
a temporary buffer that grows as necessary. */
IOBUF_OUTPUT_TEMP
};
typedef struct iobuf_struct *iobuf_t;
typedef struct iobuf_struct *IOBUF; /* Compatibility with gpg 1.4. */
/* fixme: we should hide most of this stuff */
struct iobuf_struct
{
/* The type of filter. Either IOBUF_INPUT, IOBUF_OUTPUT or
IOBUF_OUTPUT_TEMP. */
enum iobuf_use use;
/* nlimit can be changed using iobuf_set_limit. If non-zero, it is
the number of additional bytes that can be read from the filter
before EOF is forcefully returned. */
off_t nlimit;
/* nbytes if the number of bytes that have been read (using
iobuf_get / iobuf_readbyte / iobuf_read) since the last call to
iobuf_set_limit. */
off_t nbytes;
/* The number of bytes read prior to the last call to
iobuf_set_limit. Thus, the total bytes read (i.e., the position
of stream) is ntotal + nbytes. */
off_t ntotal;
/* Whether we need to read from the filter one byte at a time or
whether we can do bulk reads. We need to read one byte at a time
if a limit (set via iobuf_set_limit) is active. */
int nofast;
/* A buffer for unread/unwritten data.
For an output pipeline (IOBUF_OUTPUT), this is the data that has
not yet been written to the filter. Consider a simple pipeline
consisting of a single stage, which writes to a file. When you
write to the pipeline (iobuf_writebyte or iobuf_write), the data
is first stored in this buffer. Only when the buffer is full or
you call iobuf_flush() is FILTER actually called and the data
written to the file.
For an input pipeline (IOBUF_INPUT), this is the data that has
been read from this filter, but not yet been read from the
preceding filter (or the user, if this filter is the head of the
pipeline). Again, consider a simple pipeline consisting of a
single stage. This stage reads from a file. If you read a
single byte (iobuf_get) and the buffer is empty, then FILTER is
called to fill the buffer. In this case, a single byte is not
requested, but the whole buffer is filled (if possible). */
struct
{
/* Size of the buffer. */
size_t size;
/* Number of bytes at the beginning of the buffer that have
already been consumed. (In other words: the index of the first
byte that hasn't been consumed.) This is only non-zero for
input filters. */
size_t start;
/* The number of bytes in the buffer including any bytes that have
been consumed. */
size_t len;
/* The buffer itself. */
byte *buf;
} d;
+ /* A external drain buffer for reading/writting data skipping internal
+ draint buffer D.BUF. This allows zerocopy operation reducing
+ processing overhead across filter stack.
+
+ Used when by iobuf_read/iobuf_write when internal buffer has been
+ depleted and remaining external buffer length is large enough.
+ */
+ struct
+ {
+ /* The external buffer provided by iobuf_read/iobuf_write caller. */
+ byte *buf;
+ /* The number of bytes in the external buffer. */
+ size_t len;
+ /* The number of bytes that were consumed from the external buffer. */
+ size_t used;
+ /* Gives hint for processing that the external buffer is preferred and
+ that internal buffer should be consumed early. */
+ int preferred;
+ } e_d;
+
/* When FILTER is called to read some data, it may read some data
and then return EOF. We can't return the EOF immediately.
Instead, we note that we observed the EOF and when the buffer is
finally empty, we return the EOF. */
int filter_eof;
/* Like filter_eof, when FILTER is called to read some data, it may
read some data and then return an error. We can't return the
error (in the form of an EOF) immediately. Instead, we note that
we observed the error and when the buffer is finally empty, we
return the EOF. */
int error;
/* The callback function to read data from the filter, etc. See
iobuf_filter_push for details. */
int (*filter) (void *opaque, int control,
iobuf_t chain, byte * buf, size_t * len);
/* An opaque pointer that can be used for local filter state. This
is passed as the first parameter to FILTER. */
void *filter_ov;
/* Whether the iobuf code should free(filter_ov) when destroying the
filter. */
int filter_ov_owner;
/* When using iobuf_open, iobuf_create, iobuf_openrw to open a file,
the file's name is saved here. This is used to delete the file
when an output pipeline (IOBUF_OUPUT) is canceled
(iobuf_cancel). */
char *real_fname;
/* The next filter in the pipeline. */
iobuf_t chain;
/* This field is for debugging. Each time a filter is allocated
(via iobuf_alloc()), a monotonically increasing counter is
incremented and this field is set to the new value. This field
should only be accessed via the iobuf_io macro. */
int no;
/* The number of filters in the pipeline following (not including)
this one. When you call iobuf_push_filter or iobuf_push_filter2,
this value is used to check the length of the pipeline if the
pipeline already contains 65 stages then these functions fail.
This amount of nesting typically indicates corrupted data or an
active denial of service attack. */
int subno;
};
extern int iobuf_debug_mode;
/* Change the default size for all IOBUFs to KILOBYTE. This needs to
* be called before any iobufs are used and can only be used once.
* Returns the current value. Using 0 has no effect except for
* returning the current value. */
unsigned int iobuf_set_buffer_size (unsigned int kilobyte);
/* Returns whether the specified filename corresponds to a pipe. In
particular, this function checks if FNAME is "-" and, if special
filenames are enabled (see check_special_filename), whether
FNAME is a special filename. */
int iobuf_is_pipe_filename (const char *fname);
/* Allocate a new filter. This filter doesn't have a function
assigned to it. Thus you need to manually set IOBUF->FILTER and
IOBUF->FILTER_OV, if required. This function is intended to help
create a new primary source or primary sink, i.e., the last filter
in the pipeline.
USE is IOBUF_INPUT, IOBUF_INPUT_TEMP, IOBUF_OUTPUT or
IOBUF_OUTPUT_TEMP.
BUFSIZE is the desired internal buffer size (that is, the size of
the typical read / write request). */
iobuf_t iobuf_alloc (int use, size_t bufsize);
/* Create an output filter that simply buffers data written to it.
This is useful for collecting data for later processing. The
buffer can be written to in the usual way (iobuf_write, etc.). The
data can later be extracted using iobuf_write_temp() or
iobuf_temp_to_buffer(). */
iobuf_t iobuf_temp (void);
/* Create an input filter that contains some data for reading. */
iobuf_t iobuf_temp_with_content (const char *buffer, size_t length);
/* Create an input file filter that reads from a file. If FNAME is
'-', reads from stdin. If special filenames are enabled
(iobuf_enable_special_filenames), then interprets special
filenames. */
iobuf_t iobuf_open (const char *fname);
/* Create an output file filter that writes to a file. If FNAME is
NULL or '-', writes to stdout. If special filenames are enabled
(iobuf_enable_special_filenames), then interprets special
filenames. If FNAME is not NULL, '-' or a special filename, the
file is opened for writing. If the file exists, it is truncated.
If MODE700 is TRUE, the file is created with mode 600. Otherwise,
mode 666 is used. */
iobuf_t iobuf_create (const char *fname, int mode700);
/* Create an output file filter that writes to a specified file.
Neither '-' nor special file names are recognized. */
iobuf_t iobuf_openrw (const char *fname);
/* Create a file filter using an existing file descriptor. If MODE
contains the letter 'w', creates an output filter. Otherwise,
creates an input filter. Note: MODE must reflect the file
descriptors actual mode! When the filter is destroyed, the file
descriptor is closed. */
iobuf_t iobuf_fdopen (int fd, const char *mode);
/* Like iobuf_fdopen, but doesn't close the file descriptor when the
filter is destroyed. */
iobuf_t iobuf_fdopen_nc (int fd, const char *mode);
/* Create a filter using an existing estream. If MODE contains the
letter 'w', creates an output filter. Otherwise, creates an input
filter. If KEEP_OPEN is TRUE, then the stream is not closed when
the filter is destroyed. Otherwise, the stream is closed when the
filter is destroyed. If READLIMIT is not 0 this gives a limit on
the number of bytes to read from estream. */
iobuf_t iobuf_esopen (estream_t estream, const char *mode, int keep_open,
size_t readlimit);
/* Create a filter using an existing socket. On Windows creates a
special socket filter. On non-Windows systems simply, this simply
calls iobuf_fdopen. */
iobuf_t iobuf_sockopen (int fd, const char *mode);
/* Set various options / perform different actions on a PIPELINE. See
the IOBUF_IOCTL_* macros above. */
int iobuf_ioctl (iobuf_t a, iobuf_ioctl_t cmd, int intval, void *ptrval);
/* Close a pipeline. The filters in the pipeline are first flushed
using iobuf_flush, if they are output filters, and then
IOBUFCTRL_FREE is called on each filter.
If any filter returns a non-zero value in response to the
IOBUFCTRL_FREE, that first such non-zero value is returned. Note:
processing is not aborted in this case. If all filters are freed
successfully, 0 is returned. */
int iobuf_close (iobuf_t iobuf);
/* Calls IOBUFCTRL_CANCEL on each filter in the pipeline. Then calls
io_close() on the pipeline. Finally, if the pipeline is an output
pipeline, deletes the file. Returns the result of calling
iobuf_close on the pipeline. */
int iobuf_cancel (iobuf_t iobuf);
/* Add a new filter to the front of a pipeline. A is the head of the
pipeline. F is the filter implementation. OV is an opaque pointer
that is passed to F and is normally used to hold any internal
state, such as a file pointer.
Note: you may only maintain a reference to an iobuf_t as a
reference to the head of the pipeline. That is, don't think about
setting a pointer in OV to point to the filter's iobuf_t. This is
because when we add a new filter to a pipeline, we memcpy the state
in A into new buffer. This has the advantage that there is no need
to update any references to the pipeline when a filter is added or
removed, but it also means that a filter's state moves around in
memory.
The behavior of the filter function is determined by the value of
the control parameter:
IOBUFCTRL_INIT: Called this value just before the filter is
linked into the pipeline. This can be used to initialize
internal data structures.
IOBUFCTRL_FREE: Called with this value just before the filter is
removed from the pipeline. Normally used to release internal
data structures, close a file handle, etc.
IOBUFCTRL_UNDERFLOW: Called with this value to fill the passed
buffer with more data. *LEN is the size of the buffer. Before
returning, it should be set to the number of bytes which were
written into the buffer. The function must return 0 to
indicate success, -1 on EOF and a GPG_ERR_xxxxx code for any
error.
Note: this function may both return data and indicate an error
or EOF. In this case, it simply writes the data to BUF, sets
*LEN and returns the appropriate return code. The implication
is that if an error occurs and no data has yet been written, it
is essential that *LEN be set to 0!
IOBUFCTRL_FLUSH: Called with this value to write out any
collected data. *LEN is the number of bytes in BUF that need
to be written out. Returns 0 on success and a GPG_ERR_* code
otherwise. *LEN must be set to the number of bytes that were
written out.
IOBUFCTRL_CANCEL: Called with this value when iobuf_cancel() is
called on the pipeline.
IOBUFCTRL_DESC: Called with this value to get a human-readable
description of the filter. *LEN is the size of the buffer.
The description is filled into BUF, NUL-terminated. Always
returns 0.
*/
int iobuf_push_filter (iobuf_t a, int (*f) (void *opaque, int control,
iobuf_t chain, byte * buf,
size_t * len), void *ov);
/* This variant of iobuf_push_filter allows the called to indicate
that OV should be freed when this filter is freed. That is, if
REL_OV is TRUE, then when the filter is popped or freed OV will be
freed after the filter function is called with control set to
IOBUFCTRL_FREE. */
int iobuf_push_filter2 (iobuf_t a,
int (*f) (void *opaque, int control, iobuf_t chain,
byte * buf, size_t * len), void *ov,
int rel_ov);
/* Pop the top filter. The top filter must have the filter function F
and the cookie OV. The cookie check is ignored if OV is NULL. */
int iobuf_pop_filter (iobuf_t a,
int (*f) (void *opaque, int control,
iobuf_t chain, byte * buf, size_t * len),
void *ov);
/* Used for debugging. Prints out the chain using log_debug if
IOBUF_DEBUG_MODE is not 0. */
int iobuf_print_chain (iobuf_t a);
/* Indicate that some error occurred on the specified filter. */
#define iobuf_set_error(a) do { (a)->error = 1; } while(0)
/* Return any pending error on filter A. */
#define iobuf_error(a) ((a)->error)
/* Limit the amount of additional data that may be read from the
filter. That is, if you've already read 100 bytes from A and you
set the limit to 50, then you can read up to an additional 50 bytes
(i.e., a total of 150 bytes) before EOF is forcefully returned.
Setting NLIMIT to 0 removes any active limit.
Note: using iobuf_seek removes any currently enforced limit! */
void iobuf_set_limit (iobuf_t a, off_t nlimit);
/* Returns the number of bytes that have been read from the pipeline.
Note: the result is undefined for IOBUF_OUTPUT and IOBUF_OUTPUT_TEMP
pipelines! */
off_t iobuf_tell (iobuf_t a);
/* There are two cases:
- If A is an INPUT or OUTPUT pipeline, then the last filter in the
pipeline is found. If that is not a file filter, -1 is returned.
Otherwise, an fseek(..., SEEK_SET) is performed on the file
descriptor.
- If A is a TEMP pipeline and the *first* (and thus only filter) is
a TEMP filter, then the "file position" is effectively unchanged.
That is, data is appended to the buffer and the seek does not
cause the size of the buffer to grow.
If no error occurred, then any limit previous set by
iobuf_set_limit() is cleared. Further, any error on the filter
(the file filter or the temp filter) is cleared.
Returns 0 on success and -1 if an error occurs. */
int iobuf_seek (iobuf_t a, off_t newpos);
/* Read a single byte. If a filter has no more data, returns -1 to
indicate the EOF. Generally, you don't want to use this function,
but instead prefer the iobuf_get macro, which is faster if there is
data in the internal buffer. */
int iobuf_readbyte (iobuf_t a);
/* Get a byte from the iobuf; must check for eof prior to this
function. This function returns values in the range 0 .. 255 or -1
to indicate EOF. iobuf_get_noeof() does not return -1 to indicate
EOF, but masks the returned value to be in the range 0 .. 255. */
#define iobuf_get(a) \
( ((a)->nofast || (a)->d.start >= (a)->d.len )? \
iobuf_readbyte((a)) : ( (a)->nbytes++, (a)->d.buf[(a)->d.start++] ) )
#define iobuf_get_noeof(a) (iobuf_get((a))&0xff)
/* Fill BUF with up to BUFLEN bytes. If a filter has no more data,
returns -1 to indicate the EOF. Otherwise returns the number of
bytes read. */
int iobuf_read (iobuf_t a, void *buf, unsigned buflen);
/* Read a line of input (including the '\n') from the pipeline.
The semantics are the same as for fgets(), but if the buffer is too
short a larger one will be allocated up to *MAX_LENGTH and the end
of the line except the trailing '\n' discarded. (Thus,
*ADDR_OF_BUFFER must be allocated using malloc().) If the buffer
is enlarged, then *LENGTH_OF_BUFFER will be updated to reflect the
new size. If the line is truncated, then *MAX_LENGTH will be set
to 0. If *ADDR_OF_BUFFER is NULL, a buffer is allocated using
malloc().
A line is considered a byte stream ending in a '\n'. Returns the
number of characters written to the buffer (i.e., excluding any
discarded characters due to truncation). Thus, use this instead of
strlen(buffer) to determine the length of the string as this is
unreliable if the input contains NUL characters.
EOF is indicated by a line of length zero.
The last LF may be missing due to an EOF. */
unsigned iobuf_read_line (iobuf_t a, byte ** addr_of_buffer,
unsigned *length_of_buffer, unsigned *max_length);
/* Read up to BUFLEN bytes from pipeline A. Note: this function can't
return more than the pipeline's internal buffer size. The return
value is the number of bytes actually written to BUF. If the
filter returns EOF, then this function returns -1.
This function does not clear any pending EOF. That is, if the
pipeline consists of two filters and the first one returns EOF
during the peek, then the subsequent iobuf_read* will still return
EOF before returning the data from the second filter. */
int iobuf_peek (iobuf_t a, byte * buf, unsigned buflen);
/* Write a byte to the pipeline. Returns 0 on success and an error
code otherwise. */
int iobuf_writebyte (iobuf_t a, unsigned c);
/* Alias for iobuf_writebyte. */
#define iobuf_put(a,c) iobuf_writebyte(a,c)
/* Write a sequence of bytes to the pipeline. Returns 0 on success
and an error code otherwise. */
int iobuf_write (iobuf_t a, const void *buf, unsigned buflen);
/* Write a string (not including the NUL terminator) to the pipeline.
Returns 0 on success and an error code otherwise. */
int iobuf_writestr (iobuf_t a, const char *buf);
/* Flushes the pipeline removing all filters but the sink (the last
filter) in the process. */
void iobuf_flush_temp (iobuf_t temp);
/* Flushes the pipeline SOURCE removing all filters but the sink (the
last filter) in the process (i.e., it calls
iobuf_flush_temp(source)) and then writes the data to the pipeline
DEST. Note: this doesn't free (iobuf_close()) SOURCE. Both SOURCE
and DEST must be output pipelines. */
int iobuf_write_temp (iobuf_t dest, iobuf_t source);
/* Flushes each filter in the pipeline (i.e., sends any buffered data
to the filter by calling IOBUFCTRL_FLUSH). Then, copies up to the
first BUFLEN bytes from the last filter's internal buffer (which
will only be non-empty if it is a temp filter) to the buffer
BUFFER. Returns the number of bytes actually copied. */
size_t iobuf_temp_to_buffer (iobuf_t a, byte * buffer, size_t buflen);
/* Copies the data from the input iobuf SOURCE to the output iobuf
DEST until either an error is encountered or EOF is reached.
Returns the number of bytes successfully written. If an error
occurred, then any buffered bytes are not returned to SOURCE and are
effectively lost. To check if an error occurred, use
iobuf_error. */
size_t iobuf_copy (iobuf_t dest, iobuf_t source);
/* Return the size of any underlying file. This only works with
file_filter based pipelines.
On Win32, it is sometimes not possible to determine the size of
files larger than 4GB. In this case, *OVERFLOW (if not NULL) is
set to 1. Otherwise, *OVERFLOW is set to 0. */
off_t iobuf_get_filelength (iobuf_t a, int *overflow);
#define IOBUF_FILELENGTH_LIMIT 0xffffffff
/* Return the file descriptor designating the underlying file. This
only works with file_filter based pipelines. */
int iobuf_get_fd (iobuf_t a);
/* Return the real filename, if available. This only supports
pipelines that end in file filters. Returns NULL if not
available. */
const char *iobuf_get_real_fname (iobuf_t a);
/* Return the filename or a description thereof. For instance, for
iobuf_open("-"), this will return "[stdin]". This only supports
pipelines that end in file filters. Returns NULL if not
available. */
const char *iobuf_get_fname (iobuf_t a);
/* Like iobuf_getfname, but instead of returning NULL if no
description is available, return "[?]". */
const char *iobuf_get_fname_nonnull (iobuf_t a);
/* Pushes a filter on the pipeline that interprets the datastream as
an OpenPGP data block whose length is encoded using partial body
length headers (see Section 4.2.2.4 of RFC 4880). Concretely, it
just returns / writes the data and finishes the packet with an
EOF. */
void iobuf_set_partial_body_length_mode (iobuf_t a, size_t len);
/* If PARTIAL is set, then read from the pipeline until the first EOF
is returned.
If PARTIAL is 0, then read up to N bytes or until the first EOF is
returned.
Recall: a filter can return EOF. In this case, it and all
preceding filters are popped from the pipeline and the next read is
from the following filter (which may or may not return EOF). */
void iobuf_skip_rest (iobuf_t a, unsigned long n, int partial);
#define iobuf_where(a) "[don't know]"
/* Each time a filter is allocated (via iobuf_alloc()), a
monotonically increasing counter is incremented and this field is
set to the new value. This macro returns that number. */
#define iobuf_id(a) ((a)->no)
#define iobuf_get_temp_buffer(a) ( (a)->d.buf )
#define iobuf_get_temp_length(a) ( (a)->d.len )
/* Whether the filter uses an in-memory buffer. */
#define iobuf_is_temp(a) ( (a)->use == IOBUF_OUTPUT_TEMP )
#endif /*GNUPG_COMMON_IOBUF_H*/