The Tor Browser: security/nss/lib/zlib/gzwrite.c@b8a032363ba2 (annotated)

security/nss/lib/zlib/gzwrite.c@b8a032363ba2 (annotated)

security/nss/lib/zlib/gzwrite.c

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* gzwrite.c -- zlib functions for writing gzip files
  * Copyright (C) 2004, 2005, 2010 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 #include "gzguts.h"
 /* Local functions */
 local int gz_init OF((gz_statep));
 local int gz_comp OF((gz_statep, int));
 local int gz_zero OF((gz_statep, z_off64_t));
 /* Initialize state for writing a gzip file.  Mark initialization by setting
    state->size to non-zero.  Return -1 on failure or 0 on success. */
 local int gz_init(state)
     gz_statep state;
 {
     int ret;
     z_streamp strm = &(state->strm);
     /* allocate input and output buffers */
     state->in = malloc(state->want);
     state->out = malloc(state->want);
     if (state->in == NULL || state->out == NULL) {
         if (state->out != NULL)
             free(state->out);
         if (state->in != NULL)
             free(state->in);
         gz_error(state, Z_MEM_ERROR, "out of memory");
         return -1;
     }
     /* allocate deflate memory, set up for gzip compression */
     strm->zalloc = Z_NULL;
     strm->zfree = Z_NULL;
     strm->opaque = Z_NULL;
     ret = deflateInit2(strm, state->level, Z_DEFLATED,
 + 16, 8, state->strategy);
     if (ret != Z_OK) {
         free(state->in);
         gz_error(state, Z_MEM_ERROR, "out of memory");
         return -1;
     }
     /* mark state as initialized */
     state->size = state->want;
     /* initialize write buffer */
     strm->avail_out = state->size;
     strm->next_out = state->out;
     state->next = strm->next_out;
     return 0;
 }
 /* Compress whatever is at avail_in and next_in and write to the output file.
    Return -1 if there is an error writing to the output file, otherwise 0.
    flush is assumed to be a valid deflate() flush value.  If flush is Z_FINISH,
    then the deflate() state is reset to start a new gzip stream. */
 local int gz_comp(state, flush)
     gz_statep state;
     int flush;
 {
     int ret, got;
     unsigned have;
     z_streamp strm = &(state->strm);
     /* allocate memory if this is the first time through */
     if (state->size == 0 && gz_init(state) == -1)
         return -1;
     /* run deflate() on provided input until it produces no more output */
     ret = Z_OK;
     do {
         /* write out current buffer contents if full, or if flushing, but if
            doing Z_FINISH then don't write until we get to Z_STREAM_END */
         if (strm->avail_out == 0 || (flush != Z_NO_FLUSH &&
             (flush != Z_FINISH || ret == Z_STREAM_END))) {
             have = (unsigned)(strm->next_out - state->next);
             if (have && ((got = write(state->fd, state->next, have)) < 0 ||
                          (unsigned)got != have)) {
                 gz_error(state, Z_ERRNO, zstrerror());
                 return -1;
             }
             if (strm->avail_out == 0) {
                 strm->avail_out = state->size;
                 strm->next_out = state->out;
             }
             state->next = strm->next_out;
         }
         /* compress */
         have = strm->avail_out;
         ret = deflate(strm, flush);
         if (ret == Z_STREAM_ERROR) {
             gz_error(state, Z_STREAM_ERROR,
                       "internal error: deflate stream corrupt");
             return -1;
         }
         have -= strm->avail_out;
     } while (have);
     /* if that completed a deflate stream, allow another to start */
     if (flush == Z_FINISH)
         deflateReset(strm);
     /* all done, no errors */
     return 0;
 }
 /* Compress len zeros to output.  Return -1 on error, 0 on success. */
 local int gz_zero(state, len)
     gz_statep state;
     z_off64_t len;
 {
     int first;
     unsigned n;
     z_streamp strm = &(state->strm);
     /* consume whatever's left in the input buffer */
     if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
         return -1;
     /* compress len zeros (len guaranteed > 0) */
     first = 1;
     while (len) {
         n = GT_OFF(state->size) || (z_off64_t)state->size > len ?
             (unsigned)len : state->size;
         if (first) {
             memset(state->in, 0, n);
             first = 0;
         }
         strm->avail_in = n;
         strm->next_in = state->in;
         state->pos += n;
         if (gz_comp(state, Z_NO_FLUSH) == -1)
             return -1;
         len -= n;
     }
     return 0;
 }
 /* -- see zlib.h -- */
 int ZEXPORT gzwrite(file, buf, len)
     gzFile file;
     voidpc buf;
     unsigned len;
 {
     unsigned put = len;
     unsigned n;
     gz_statep state;
     z_streamp strm;
     /* get internal structure */
     if (file == NULL)
         return 0;
     state = (gz_statep)file;
     strm = &(state->strm);
     /* check that we're writing and that there's no error */
     if (state->mode != GZ_WRITE || state->err != Z_OK)
         return 0;
     /* since an int is returned, make sure len fits in one, otherwise return
        with an error (this avoids the flaw in the interface) */
     if ((int)len < 0) {
         gz_error(state, Z_BUF_ERROR, "requested length does not fit in int");
         return 0;
     }
     /* if len is zero, avoid unnecessary operations */
     if (len == 0)
         return 0;
     /* allocate memory if this is the first time through */
     if (state->size == 0 && gz_init(state) == -1)
         return 0;
     /* check for seek request */
     if (state->seek) {
         state->seek = 0;
         if (gz_zero(state, state->skip) == -1)
             return 0;
     }
     /* for small len, copy to input buffer, otherwise compress directly */
     if (len < state->size) {
         /* copy to input buffer, compress when full */
         do {
             if (strm->avail_in == 0)
                 strm->next_in = state->in;
             n = state->size - strm->avail_in;
             if (n > len)
                 n = len;
             memcpy(strm->next_in + strm->avail_in, buf, n);
             strm->avail_in += n;
             state->pos += n;
             buf = (char *)buf + n;
             len -= n;
             if (len && gz_comp(state, Z_NO_FLUSH) == -1)
                 return 0;
         } while (len);
     }
     else {
         /* consume whatever's left in the input buffer */
         if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
             return 0;
         /* directly compress user buffer to file */
         strm->avail_in = len;
         strm->next_in = (voidp)buf;
         state->pos += len;
         if (gz_comp(state, Z_NO_FLUSH) == -1)
             return 0;
     }
     /* input was all buffered or compressed (put will fit in int) */
     return (int)put;
 }
 /* -- see zlib.h -- */
 int ZEXPORT gzputc(file, c)
     gzFile file;
     int c;
 {
     unsigned char buf[1];
     gz_statep state;
     z_streamp strm;
     /* get internal structure */
     if (file == NULL)
         return -1;
     state = (gz_statep)file;
     strm = &(state->strm);
     /* check that we're writing and that there's no error */
     if (state->mode != GZ_WRITE || state->err != Z_OK)
         return -1;
     /* check for seek request */
     if (state->seek) {
         state->seek = 0;
         if (gz_zero(state, state->skip) == -1)
             return -1;
     }
     /* try writing to input buffer for speed (state->size == 0 if buffer not
        initialized) */
     if (strm->avail_in < state->size) {
         if (strm->avail_in == 0)
             strm->next_in = state->in;
         strm->next_in[strm->avail_in++] = c;
         state->pos++;
         return c;
     }
     /* no room in buffer or not initialized, use gz_write() */
     buf[0] = c;
     if (gzwrite(file, buf, 1) != 1)
         return -1;
     return c;
 }
 /* -- see zlib.h -- */
 int ZEXPORT gzputs(file, str)
     gzFile file;
     const char *str;
 {
     int ret;
     unsigned len;
     /* write string */
     len = (unsigned)strlen(str);
     ret = gzwrite(file, str, len);
     return ret == 0 && len != 0 ? -1 : ret;
 }
 #ifdef STDC
 #include <stdarg.h>
 /* -- see zlib.h -- */
 int ZEXPORTVA gzprintf (gzFile file, const char *format, ...)
 {
     int size, len;
     gz_statep state;
     z_streamp strm;
     va_list va;
     /* get internal structure */
     if (file == NULL)
         return -1;
     state = (gz_statep)file;
     strm = &(state->strm);
     /* check that we're writing and that there's no error */
     if (state->mode != GZ_WRITE || state->err != Z_OK)
         return 0;
     /* make sure we have some buffer space */
     if (state->size == 0 && gz_init(state) == -1)
         return 0;
     /* check for seek request */
     if (state->seek) {
         state->seek = 0;
         if (gz_zero(state, state->skip) == -1)
             return 0;
     }
     /* consume whatever's left in the input buffer */
     if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
         return 0;
     /* do the printf() into the input buffer, put length in len */
     size = (int)(state->size);
     state->in[size - 1] = 0;
     va_start(va, format);
 #ifdef NO_vsnprintf
 #  ifdef HAS_vsprintf_void
     (void)vsprintf(state->in, format, va);
     va_end(va);
     for (len = 0; len < size; len++)
         if (state->in[len] == 0) break;
 #  else
     len = vsprintf(state->in, format, va);
     va_end(va);
 #  endif
 #else
 #  ifdef HAS_vsnprintf_void
     (void)vsnprintf(state->in, size, format, va);
     va_end(va);
     len = strlen(state->in);
 #  else
     len = vsnprintf((char *)(state->in), size, format, va);
     va_end(va);
 #  endif
 #endif
     /* check that printf() results fit in buffer */
     if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
         return 0;
     /* update buffer and position, defer compression until needed */
     strm->avail_in = (unsigned)len;
     strm->next_in = state->in;
     state->pos += len;
     return len;
 }
 #else /* !STDC */
 /* -- see zlib.h -- */
 int ZEXPORTVA gzprintf (file, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
                        a11, a12, a13, a14, a15, a16, a17, a18, a19, a20)
     gzFile file;
     const char *format;
     int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
         a11, a12, a13, a14, a15, a16, a17, a18, a19, a20;
 {
     int size, len;
     gz_statep state;
     z_streamp strm;
     /* get internal structure */
     if (file == NULL)
         return -1;
     state = (gz_statep)file;
     strm = &(state->strm);
     /* check that we're writing and that there's no error */
     if (state->mode != GZ_WRITE || state->err != Z_OK)
         return 0;
     /* make sure we have some buffer space */
     if (state->size == 0 && gz_init(state) == -1)
         return 0;
     /* check for seek request */
     if (state->seek) {
         state->seek = 0;
         if (gz_zero(state, state->skip) == -1)
             return 0;
     }
     /* consume whatever's left in the input buffer */
     if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
         return 0;
     /* do the printf() into the input buffer, put length in len */
     size = (int)(state->size);
     state->in[size - 1] = 0;
 #ifdef NO_snprintf
 #  ifdef HAS_sprintf_void
     sprintf(state->in, format, a1, a2, a3, a4, a5, a6, a7, a8,
             a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
     for (len = 0; len < size; len++)
         if (state->in[len] == 0) break;
 #  else
     len = sprintf(state->in, format, a1, a2, a3, a4, a5, a6, a7, a8,
                 a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
 #  endif
 #else
 #  ifdef HAS_snprintf_void
     snprintf(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8,
              a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
     len = strlen(state->in);
 #  else
     len = snprintf(state->in, size, format, a1, a2, a3, a4, a5, a6, a7, a8,
                  a9, a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
 #  endif
 #endif
     /* check that printf() results fit in buffer */
     if (len <= 0 || len >= (int)size || state->in[size - 1] != 0)
         return 0;
     /* update buffer and position, defer compression until needed */
     strm->avail_in = (unsigned)len;
     strm->next_in = state->in;
     state->pos += len;
     return len;
 }
 #endif
 /* -- see zlib.h -- */
 int ZEXPORT gzflush(file, flush)
     gzFile file;
     int flush;
 {
     gz_statep state;
     /* get internal structure */
     if (file == NULL)
         return -1;
     state = (gz_statep)file;
     /* check that we're writing and that there's no error */
     if (state->mode != GZ_WRITE || state->err != Z_OK)
         return Z_STREAM_ERROR;
     /* check flush parameter */
     if (flush < 0 || flush > Z_FINISH)
         return Z_STREAM_ERROR;
     /* check for seek request */
     if (state->seek) {
         state->seek = 0;
         if (gz_zero(state, state->skip) == -1)
             return -1;
     }
     /* compress remaining data with requested flush */
     gz_comp(state, flush);
     return state->err;
 }
 /* -- see zlib.h -- */
 int ZEXPORT gzsetparams(file, level, strategy)
     gzFile file;
     int level;
     int strategy;
 {
     gz_statep state;
     z_streamp strm;
     /* get internal structure */
     if (file == NULL)
         return Z_STREAM_ERROR;
     state = (gz_statep)file;
     strm = &(state->strm);
     /* check that we're writing and that there's no error */
     if (state->mode != GZ_WRITE || state->err != Z_OK)
         return Z_STREAM_ERROR;
     /* if no change is requested, then do nothing */
     if (level == state->level && strategy == state->strategy)
         return Z_OK;
     /* check for seek request */
     if (state->seek) {
         state->seek = 0;
         if (gz_zero(state, state->skip) == -1)
             return -1;
     }
     /* change compression parameters for subsequent input */
     if (state->size) {
         /* flush previous input with previous parameters before changing */
         if (strm->avail_in && gz_comp(state, Z_PARTIAL_FLUSH) == -1)
             return state->err;
         deflateParams(strm, level, strategy);
     }
     state->level = level;
     state->strategy = strategy;
     return Z_OK;
 }
 /* -- see zlib.h -- */
 int ZEXPORT gzclose_w(file)
     gzFile file;
 {
     int ret = 0;
     gz_statep state;
     /* get internal structure */
     if (file == NULL)
         return Z_STREAM_ERROR;
     state = (gz_statep)file;
     /* check that we're writing */
     if (state->mode != GZ_WRITE)
         return Z_STREAM_ERROR;
     /* check for seek request */
     if (state->seek) {
         state->seek = 0;
         ret += gz_zero(state, state->skip);
     }
     /* flush, free memory, and close file */
     ret += gz_comp(state, Z_FINISH);
     (void)deflateEnd(&(state->strm));
     free(state->out);
     free(state->in);
     gz_error(state, Z_OK, NULL);
     free(state->path);
     ret += close(state->fd);
     free(state);
     return ret ? Z_ERRNO : Z_OK;
 }

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security/nss/lib/zlib/gzwrite.c@b8a032363ba2 (annotated)

security/nss/lib/zlib/gzwrite.c