Update zlib to 1.2.11

third_party/zlib/gzread.c

 /* gzread.c -- zlib functions for reading gzip files
- * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013 Mark Adler
+ * Copyright (C) 2004, 2005, 2010, 2011, 2012, 2013, 2016 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
 #include "gzguts.h"
 
 /* Local functions */
 local int gz_load OF((gz_statep, unsigned char *, unsigned, unsigned *));
 local int gz_avail OF((gz_statep));
 local int gz_look OF((gz_statep));
 local int gz_decomp OF((gz_statep));
 local int gz_fetch OF((gz_statep));
 local int gz_skip OF((gz_statep, z_off64_t));
+local z_size_t gz_read OF((gz_statep, voidp, z_size_t));
 
 /* Use read() to load a buffer -- return -1 on error, otherwise 0.  Read from
    state->fd, and update state->eof, state->err, and state->msg as appropriate.
    This function needs to loop on read(), since read() is not guaranteed to
    read the number of bytes requested, depending on the type of descriptor. */
 local int gz_load(state, buf, len, have)
     gz_statep state;
     unsigned char *buf;
     unsigned len;
     unsigned *have;
 {
     int ret;
+    unsigned get, max = ((unsigned)-1 >> 2) + 1;
 
     *have = 0;
     do {
-        ret = read(state->fd, buf + *have, len - *have);
+        get = len - *have;
+        if (get > max)
+            get = max;
+        ret = read(state->fd, buf + *have, get);
         if (ret <= 0)
             break;
-        *have += ret;
+        *have += (unsigned)ret;
     } while (*have < len);
     if (ret < 0) {
         gz_error(state, Z_ERRNO, zstrerror());
         return -1;
     }
     if (ret == 0)
         state->eof = 1;
     return 0;
 }
 
@@ skipping 43 matching lines @@
     gz_statep state;
 {
     z_streamp strm = &(state->strm);
 
     /* allocate read buffers and inflate memory */
     if (state->size == 0) {
         /* allocate buffers */
         state->in = (unsigned char *)malloc(state->want);
         state->out = (unsigned char *)malloc(state->want << 1);
         if (state->in == NULL || state->out == NULL) {
-            if (state->out != NULL)
-                free(state->out);
-            if (state->in != NULL)
-                free(state->in);
+            free(state->out);
+            free(state->in);
             gz_error(state, Z_MEM_ERROR, "out of memory");
             return -1;
         }
         state->size = state->want;
 
         /* allocate inflate memory */
         state->strm.zalloc = Z_NULL;
         state->strm.zfree = Z_NULL;
         state->strm.opaque = Z_NULL;
         state->strm.avail_in = 0;
@@ skipping 166 matching lines @@
 
         /* need more data to skip -- load up output buffer */
         else {
             /* get more output, looking for header if required */
             if (gz_fetch(state) == -1)
                 return -1;
         }
     return 0;
 }
 
-/* -- see zlib.h -- */
-int ZEXPORT gzread(file, buf, len)
-    gzFile file;
+/* Read len bytes into buf from file, or less than len up to the end of the
+   input.  Return the number of bytes read.  If zero is returned, either the
+   end of file was reached, or there was an error.  state->err must be
+   consulted in that case to determine which. */
+local z_size_t gz_read(state, buf, len)
+    gz_statep state;
     voidp buf;
-    unsigned len;
+    z_size_t len;
 {
-    unsigned got, n;
-    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 reading and that there's no (serious) error */
-    if (state->mode != GZ_READ ||
-            (state->err != Z_OK && state->err != Z_BUF_ERROR))
-        return -1;
-
-    /* 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_DATA_ERROR, "requested length does not fit in int");
-        return -1;
-    }
+    z_size_t got;
+    unsigned n;
 
     /* if len is zero, avoid unnecessary operations */
     if (len == 0)
         return 0;
 
     /* process a skip request */
     if (state->seek) {
         state->seek = 0;
         if (gz_skip(state, state->skip) == -1)
-            return -1;
+            return 0;
     }
 
     /* get len bytes to buf, or less than len if at the end */
     got = 0;
     do {
+        /* set n to the maximum amount of len that fits in an unsigned int */
+        n = -1;
+        if (n > len)
+            n = len;
+
         /* first just try copying data from the output buffer */
         if (state->x.have) {
-            n = state->x.have > len ? len : state->x.have;
+            if (state->x.have < n)
+                n = state->x.have;
             memcpy(buf, state->x.next, n);
             state->x.next += n;
             state->x.have -= n;
         }
 
         /* output buffer empty -- return if we're at the end of the input */
-        else if (state->eof && strm->avail_in == 0) {
+        else if (state->eof && state->strm.avail_in == 0) {
             state->past = 1;        /* tried to read past end */
             break;
         }
 
         /* need output data -- for small len or new stream load up our output
            buffer */
-        else if (state->how == LOOK || len < (state->size << 1)) {
+        else if (state->how == LOOK || n < (state->size << 1)) {
             /* get more output, looking for header if required */
             if (gz_fetch(state) == -1)
-                return -1;
+                return 0;
             continue;       /* no progress yet -- go back to copy above */
             /* the copy above assures that we will leave with space in the
                output buffer, allowing at least one gzungetc() to succeed */
         }
 
         /* large len -- read directly into user buffer */
         else if (state->how == COPY) {      /* read directly */
-            if (gz_load(state, (unsigned char *)buf, len, &n) == -1)
-                return -1;
+            if (gz_load(state, (unsigned char *)buf, n, &n) == -1)
+                return 0;
         }
 
         /* large len -- decompress directly into user buffer */
         else {  /* state->how == GZIP */
-            strm->avail_out = len;
-            strm->next_out = (unsigned char *)buf;
+            state->strm.avail_out = n;
+            state->strm.next_out = (unsigned char *)buf;
             if (gz_decomp(state) == -1)
-                return -1;
+                return 0;
             n = state->x.have;
             state->x.have = 0;
         }
 
         /* update progress */
         len -= n;
         buf = (char *)buf + n;
         got += n;
         state->x.pos += n;
     } while (len);
 
-    /* return number of bytes read into user buffer (will fit in int) */
-    return (int)got;
+    /* return number of bytes read into user buffer */
+    return got;
 }
 
 /* -- see zlib.h -- */
+int ZEXPORT gzread(file, buf, len)
+    gzFile file;
+    voidp buf;
+    unsigned len;
+{
+    gz_statep state;
+
+    /* get internal structure */
+    if (file == NULL)
+        return -1;
+    state = (gz_statep)file;
+
+    /* check that we're reading and that there's no (serious) error */
+    if (state->mode != GZ_READ ||
+            (state->err != Z_OK && state->err != Z_BUF_ERROR))
+        return -1;
+
+    /* since an int is returned, make sure len fits in one, otherwise return
+       with an error (this avoids a flaw in the interface) */
+    if ((int)len < 0) {
+        gz_error(state, Z_STREAM_ERROR, "request does not fit in an int");
+        return -1;
+    }
+
+    /* read len or fewer bytes to buf */
+    len = gz_read(state, buf, len);
+
+    /* check for an error */
+    if (len == 0 && state->err != Z_OK && state->err != Z_BUF_ERROR)
+        return -1;
+
+    /* return the number of bytes read (this is assured to fit in an int) */
+    return (int)len;
+}
+
+/* -- see zlib.h -- */
+z_size_t ZEXPORT gzfread(buf, size, nitems, file)
+    voidp buf;
+    z_size_t size;
+    z_size_t nitems;
+    gzFile file;
+{
+    z_size_t len;
+    gz_statep state;
+
+    /* get internal structure */
+    if (file == NULL)
+        return 0;
+    state = (gz_statep)file;
+
+    /* check that we're reading and that there's no (serious) error */
+    if (state->mode != GZ_READ ||
+            (state->err != Z_OK && state->err != Z_BUF_ERROR))
+        return 0;
+
+    /* compute bytes to read -- error on overflow */
+    len = nitems * size;
+    if (size && len / size != nitems) {
+        gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
+        return 0;
+    }
+
+    /* read len or fewer bytes to buf, return the number of full items read */
+    return len ? gz_read(state, buf, len) / size : 0;
+}
+
+/* -- see zlib.h -- */
 #ifdef Z_PREFIX_SET
 #  undef z_gzgetc
 #else
 #  undef gzgetc
-#  ifdef MOZZCONF_H
-#    define gzgetc MOZ_Z_gzgetc
+#  ifdef Z_CR_PREFIX_SET
+#    define gzgetc Cr_z_gzgetc
 #  endif
 #endif
 
 int ZEXPORT gzgetc(file)
     gzFile file;
 {
     int ret;
     unsigned char buf[1];
     gz_statep state;
 
     /* get internal structure */
     if (file == NULL)
         return -1;
     state = (gz_statep)file;
 
     /* check that we're reading and that there's no (serious) error */
     if (state->mode != GZ_READ ||
         (state->err != Z_OK && state->err != Z_BUF_ERROR))
         return -1;
 
     /* try output buffer (no need to check for skip request) */
     if (state->x.have) {
         state->x.have--;
         state->x.pos++;
         return *(state->x.next)++;
     }
 
-    /* nothing there -- try gzread() */
-    ret = gzread(file, buf, 1);
+    /* nothing there -- try gz_read() */
+    ret = gz_read(state, buf, 1);
     return ret < 1 ? -1 : buf[0];
 }
 
 int ZEXPORT gzgetc_(file)
 gzFile file;
 {
     return gzgetc(file);
 }
 
 /* -- see zlib.h -- */
@@ skipping 21 matching lines @@
     }
 
     /* can't push EOF */
     if (c < 0)
         return -1;
 
     /* if output buffer empty, put byte at end (allows more pushing) */
     if (state->x.have == 0) {
         state->x.have = 1;
         state->x.next = state->out + (state->size << 1) - 1;
-        state->x.next[0] = c;
+        state->x.next[0] = (unsigned char)c;
         state->x.pos--;
         state->past = 0;
         return c;
     }
 
     /* if no room, give up (must have already done a gzungetc()) */
     if (state->x.have == (state->size << 1)) {
         gz_error(state, Z_DATA_ERROR, "out of room to push characters");
         return -1;
     }
 
     /* slide output data if needed and insert byte before existing data */
     if (state->x.next == state->out) {
         unsigned char *src = state->out + state->x.have;
         unsigned char *dest = state->out + (state->size << 1);
         while (src > state->out)
             *--dest = *--src;
         state->x.next = dest;
     }
     state->x.have++;
     state->x.next--;
-    state->x.next[0] = c;
+    state->x.next[0] = (unsigned char)c;
     state->x.pos--;
     state->past = 0;
     return c;
 }
 
 /* -- see zlib.h -- */
 char * ZEXPORT gzgets(file, buf, len)
     gzFile file;
     char *buf;
     int len;
@@ skipping 98 matching lines @@
         free(state->out);
         free(state->in);
     }
     err = state->err == Z_BUF_ERROR ? Z_BUF_ERROR : Z_OK;
     gz_error(state, Z_OK, NULL);
     free(state->path);
     ret = close(state->fd);
     free(state);
     return ret ? Z_ERRNO : err;
 }