Add gzfwrite(), duplicating the interface of fwrite().
diff --git a/gzwrite.c b/gzwrite.c
index eb73d9c..2420514 100644
--- a/gzwrite.c
+++ b/gzwrite.c
@@ -9,6 +9,7 @@
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));
+local z_size_t gz_write OF((gz_statep, voidpc, z_size_t));
/* Initialize state for writing a gzip file. Mark initialization by setting
state->size to non-zero. Return -1 on a memory allocation failure, or 0 on
@@ -170,32 +171,14 @@
return 0;
}
-/* -- see zlib.h -- */
-int ZEXPORT gzwrite(file, buf, len)
- gzFile file;
- voidpc buf;
- unsigned len;
-{
- unsigned put = len;
+/* Write len bytes from buf to file. Return the number of bytes written. If
+ the returned value is less than len, then there was an error. */
+local z_size_t gz_write(state, buf, len)
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_DATA_ERROR, "requested length does not fit in int");
- return 0;
- }
+ voidpc buf;
+ z_size_t len;
+{
+ z_size_t put = len;
/* if len is zero, avoid unnecessary operations */
if (len == 0)
@@ -218,14 +201,15 @@
do {
unsigned have, copy;
- if (strm->avail_in == 0)
- strm->next_in = state->in;
- have = (unsigned)((strm->next_in + strm->avail_in) - state->in);
+ if (state->strm.avail_in == 0)
+ state->strm.next_in = state->in;
+ have = (unsigned)((state->strm.next_in + state->strm.avail_in) -
+ state->in);
copy = state->size - have;
if (copy > len)
copy = len;
memcpy(state->in + have, buf, copy);
- strm->avail_in += copy;
+ state->strm.avail_in += copy;
state->x.pos += copy;
buf = (const char *)buf + copy;
len -= copy;
@@ -235,19 +219,83 @@
}
else {
/* consume whatever's left in the input buffer */
- if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
+ if (state->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 = (z_const Bytef *)buf;
- state->x.pos += len;
- if (gz_comp(state, Z_NO_FLUSH) == -1)
- return 0;
+ state->strm.next_in = (z_const Bytef *)buf;
+ do {
+ unsigned n = -1;
+ if (n > len)
+ n = len;
+ state->strm.avail_in = n;
+ state->x.pos += n;
+ if (gz_comp(state, Z_NO_FLUSH) == -1)
+ return 0;
+ len -= n;
+ } while (len);
}
- /* input was all buffered or compressed (put will fit in int) */
- return (int)put;
+ /* input was all buffered or compressed */
+ return put;
+}
+
+/* -- see zlib.h -- */
+int ZEXPORT gzwrite(file, buf, len)
+ gzFile file;
+ voidpc buf;
+ unsigned len;
+{
+ gz_statep state;
+
+ /* get internal structure */
+ if (file == NULL)
+ return 0;
+ 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 0;
+
+ /* 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_DATA_ERROR, "requested length does not fit in int");
+ return 0;
+ }
+
+ /* write len bytes from buf (the return value will fit in an int) */
+ return (int)gz_write(state, buf, len);
+}
+
+/* -- see zlib.h -- */
+z_size_t ZEXPORT gzfwrite(buf, size, nitems, file)
+ voidpc 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 writing and that there's no error */
+ if (state->mode != GZ_WRITE || state->err != Z_OK)
+ 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;
+ }
+
+ /* write len bytes to buf, return the number of full items written */
+ return len ? gz_write(state, buf, len) / size : 0;
}
/* -- see zlib.h -- */
@@ -293,7 +341,7 @@
/* no room in buffer or not initialized, use gz_write() */
buf[0] = (unsigned char)c;
- if (gzwrite(file, buf, 1) != 1)
+ if (gz_write(state, buf, 1) != 1)
return -1;
return c & 0xff;
}
@@ -304,11 +352,21 @@
const char *str;
{
int ret;
- unsigned len;
+ z_size_t len;
+ 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 -1;
/* write string */
- len = (unsigned)strlen(str);
- ret = gzwrite(file, str, len);
+ len = strlen(str);
+ ret = gz_write(state, str, len);
return ret == 0 && len != 0 ? -1 : ret;
}
diff --git a/zlib.h b/zlib.h
index ff4469d..053e6e2 100644
--- a/zlib.h
+++ b/zlib.h
@@ -1427,6 +1427,20 @@
error.
*/
+ZEXTERN z_size_t ZEXPORT gzfwrite OF((voidpc buf, z_size_t size,
+ z_size_t nitems, gzFile file));
+/*
+ gzfwrite() writes nitems items of size size from buf to file, duplicating
+ the interface of stdio's fwrite(), with size_t request and return types. If
+ the library defines size_t, then z_size_t is identical to size_t. If not,
+ then z_size_t is an unsigned integer type that can contain a pointer.
+
+ gzfwrite() returns the number of full items written of size size, or zero
+ if there was an error. If the multiplication of size and nitems overflows,
+ i.e. the product does not fit in a z_size_t, then nothing is written, zero
+ is returned, and the error state is set to Z_STREAM_ERROR.
+*/
+
ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
/*
Converts, formats, and writes the arguments to the compressed file under
