Update zlib to 1.2.11

third_party/zlib/gzlib.c

 /* gzlib.c -- zlib functions common to reading and writing gzip files
- * Copyright (C) 2004, 2010, 2011, 2012, 2013 Mark Adler
+ * Copyright (C) 2004-2017 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
 #include "gzguts.h"
 
-#if defined(_WIN32) && !defined(__BORLANDC__)
+#if defined(_WIN32) && !defined(__BORLANDC__) && !defined(__MINGW32__)
 #  define LSEEK _lseeki64
 #else
 #if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
 #  define LSEEK lseek64
 #else
 #  define LSEEK lseek
 #endif
 #endif
 
 /* Local functions */
@@ skipping 68 matching lines @@
     state->strm.avail_in = 0;       /* no input data yet */
 }
 
 /* Open a gzip file either by name or file descriptor. */
 local gzFile gz_open(path, fd, mode)
     const void *path;
     int fd;
     const char *mode;
 {
     gz_statep state;
-    size_t len;
+    z_size_t len;
     int oflag;
 #ifdef O_CLOEXEC
     int cloexec = 0;
 #endif
 #ifdef O_EXCL
     int exclusive = 0;
 #endif
 
     /* check input */
     if (path == NULL)
@@ skipping 73 matching lines @@
     /* can't force transparent read */
     if (state->mode == GZ_READ) {
         if (state->direct) {
             free(state);
             return NULL;
         }
         state->direct = 1;      /* for empty file */
     }
 
     /* save the path name for error messages */
-#ifdef _WIN32
+#ifdef WIDECHAR
     if (fd == -2) {
         len = wcstombs(NULL, path, 0);
-        if (len == (size_t)-1)
+        if (len == (z_size_t)-1)
             len = 0;
     }
     else
 #endif
         len = strlen((const char *)path);
     state->path = (char *)malloc(len + 1);
     if (state->path == NULL) {
         free(state);
         return NULL;
     }
-#ifdef _WIN32
+#ifdef WIDECHAR
     if (fd == -2)
         if (len)
             wcstombs(state->path, path, len + 1);
         else
             *(state->path) = 0;
     else
 #endif
 #if !defined(NO_snprintf) && !defined(NO_vsnprintf)
-        snprintf(state->path, len + 1, "%s", (const char *)path);
+        (void)snprintf(state->path, len + 1, "%s", (const char *)path);
 #else
         strcpy(state->path, path);
 #endif
 
     /* compute the flags for open() */
     oflag =
 #ifdef O_LARGEFILE
         O_LARGEFILE |
 #endif
 #ifdef O_BINARY
         O_BINARY |
 #endif
 #ifdef O_CLOEXEC
         (cloexec ? O_CLOEXEC : 0) |
 #endif
         (state->mode == GZ_READ ?
          O_RDONLY :
          (O_WRONLY | O_CREAT |
 #ifdef O_EXCL
           (exclusive ? O_EXCL : 0) |
 #endif
           (state->mode == GZ_WRITE ?
            O_TRUNC :
            O_APPEND)));
 
     /* open the file with the appropriate flags (or just use fd) */
     state->fd = fd > -1 ? fd : (
-#ifdef _WIN32
+#ifdef WIDECHAR
         fd == -2 ? _wopen(path, oflag, 0666) :
 #endif
         open((const char *)path, oflag, 0666));
     if (state->fd == -1) {
         free(state->path);
         free(state);
         return NULL;
     }
-    if (state->mode == GZ_APPEND)
+    if (state->mode == GZ_APPEND) {
+        LSEEK(state->fd, 0, SEEK_END);  /* so gzoffset() is correct */
         state->mode = GZ_WRITE;         /* simplify later checks */
+    }
 
     /* save the current position for rewinding (only if reading) */
     if (state->mode == GZ_READ) {
         state->start = LSEEK(state->fd, 0, SEEK_CUR);
         if (state->start == -1) state->start = 0;
     }
 
     /* initialize stream */
     gz_reset(state);
 
@@ skipping 21 matching lines @@
 gzFile ZEXPORT gzdopen(fd, mode)
     int fd;
     const char *mode;
 {
     char *path;         /* identifier for error messages */
     gzFile gz;
 
     if (fd == -1 || (path = (char *)malloc(7 + 3 * sizeof(int))) == NULL)
         return NULL;
 #if !defined(NO_snprintf) && !defined(NO_vsnprintf)
-    snprintf(path, 7 + 3 * sizeof(int), "<fd:%d>", fd); /* for debugging */
+    (void)snprintf(path, 7 + 3 * sizeof(int), "<fd:%d>", fd);
 #else
     sprintf(path, "<fd:%d>", fd);   /* for debugging */
 #endif
     gz = gz_open(path, fd, mode);
     free(path);
     return gz;
 }
 
 /* -- see zlib.h -- */
-#ifdef _WIN32
+#ifdef WIDECHAR
 gzFile ZEXPORT gzopen_w(path, mode)
     const wchar_t *path;
     const char *mode;
 {
     return gz_open(path, -2, mode);
 }
 #endif
 
 /* -- see zlib.h -- */
 int ZEXPORT gzbuffer(file, size)
     gzFile file;
     unsigned size;
 {
     gz_statep state;
 
     /* get internal structure and check integrity */
     if (file == NULL)
         return -1;
     state = (gz_statep)file;
     if (state->mode != GZ_READ && state->mode != GZ_WRITE)
         return -1;
 
     /* make sure we haven't already allocated memory */
     if (state->size != 0)
         return -1;
 
     /* check and set requested size */
+    if ((size << 1) < size)
+        return -1;              /* need to be able to double it */
     if (size < 2)
         size = 2;               /* need two bytes to check magic header */
     state->want = size;
     return 0;
 }
 
 /* -- see zlib.h -- */
 int ZEXPORT gzrewind(file)
     gzFile file;
 {
@@ skipping 255 matching lines @@
     if (err == Z_MEM_ERROR)
         return;
 
     /* construct error message with path */
     if ((state->msg = (char *)malloc(strlen(state->path) + strlen(msg) + 3)) ==
             NULL) {
         state->err = Z_MEM_ERROR;
         return;
     }
 #if !defined(NO_snprintf) && !defined(NO_vsnprintf)
-    snprintf(state->msg, strlen(state->path) + strlen(msg) + 3,
-             "%s%s%s", state->path, ": ", msg);
+    (void)snprintf(state->msg, strlen(state->path) + strlen(msg) + 3,
+                   "%s%s%s", state->path, ": ", msg);
 #else
     strcpy(state->msg, state->path);
     strcat(state->msg, ": ");
     strcat(state->msg, msg);
 #endif
-    return;
 }
 
 #ifndef INT_MAX
 /* portably return maximum value for an int (when limits.h presumed not
    available) -- we need to do this to cover cases where 2's complement not
    used, since C standard permits 1's complement and sign-bit representations,
    otherwise we could just use ((unsigned)-1) >> 1 */
 unsigned ZLIB_INTERNAL gz_intmax()
 {
     unsigned p, q;
 
     p = 1;
     do {
         q = p;
         p <<= 1;
         p++;
     } while (p > q);
     return q >> 1;
 }
 #endif