* a Linking Exception. For full terms see the included COPYING file.
*/
+#include "zstream.h"
+
#include <zlib.h>
-#include "zstream.h"
#include "buffer.h"
-#define BUFFER_SIZE (1024 * 1024)
+#define ZSTREAM_BUFFER_SIZE (1024 * 1024)
+#define ZSTREAM_BUFFER_MIN_EXTRA 8
-static int zstream_seterr(int zerr, git_zstream *zstream)
+GIT_INLINE(int) zstream_seterr(git_zstream *zs)
{
- if (zerr == Z_MEM_ERROR)
- giterr_set_oom();
- else if (zstream->msg)
- giterr_set(GITERR_ZLIB, zstream->msg);
- else
- giterr_set(GITERR_ZLIB, "Unknown compression error");
+ switch (zs->zerr) {
+ case Z_OK:
+ case Z_STREAM_END:
+ case Z_BUF_ERROR: /* not fatal; we retry with a larger buffer */
+ return 0;
+ case Z_MEM_ERROR:
+ git_error_set_oom();
+ break;
+ default:
+ if (zs->z.msg)
+ git_error_set_str(GIT_ERROR_ZLIB, zs->z.msg);
+ else
+ git_error_set(GIT_ERROR_ZLIB, "unknown compression error");
+ }
return -1;
}
-int git_zstream_init(git_zstream *zstream)
+int git_zstream_init(git_zstream *zstream, git_zstream_t type)
{
- int zerr;
+ zstream->type = type;
- if ((zerr = deflateInit(zstream, Z_DEFAULT_COMPRESSION)) != Z_OK)
- return zstream_seterr(zerr, zstream);
+ if (zstream->type == GIT_ZSTREAM_INFLATE)
+ zstream->zerr = inflateInit(&zstream->z);
+ else
+ zstream->zerr = deflateInit(&zstream->z, Z_DEFAULT_COMPRESSION);
+ return zstream_seterr(zstream);
+}
- return 0;
+void git_zstream_free(git_zstream *zstream)
+{
+ if (zstream->type == GIT_ZSTREAM_INFLATE)
+ inflateEnd(&zstream->z);
+ else
+ deflateEnd(&zstream->z);
}
-ssize_t git_zstream_deflate(void *out, size_t out_len, git_zstream *zstream, const void *in, size_t in_len)
+void git_zstream_reset(git_zstream *zstream)
{
- int zerr;
+ if (zstream->type == GIT_ZSTREAM_INFLATE)
+ inflateReset(&zstream->z);
+ else
+ deflateReset(&zstream->z);
+ zstream->in = NULL;
+ zstream->in_len = 0;
+ zstream->zerr = Z_STREAM_END;
+}
- if ((ssize_t)out_len < 0)
- out_len = INT_MAX;
+int git_zstream_set_input(git_zstream *zstream, const void *in, size_t in_len)
+{
+ zstream->in = in;
+ zstream->in_len = in_len;
+ zstream->zerr = Z_OK;
+ return 0;
+}
- zstream->next_in = (Bytef *)in;
- zstream->avail_in = in_len;
- zstream->next_out = out;
- zstream->avail_out = out_len;
+bool git_zstream_done(git_zstream *zstream)
+{
+ return (!zstream->in_len && zstream->zerr == Z_STREAM_END);
+}
- if ((zerr = deflate(zstream, Z_FINISH)) == Z_STREAM_ERROR)
- return zstream_seterr(zerr, zstream);
+bool git_zstream_eos(git_zstream *zstream)
+{
+ return zstream->zerr == Z_STREAM_END;
+}
- return (out_len - zstream->avail_out);
+size_t git_zstream_suggest_output_len(git_zstream *zstream)
+{
+ if (zstream->in_len > ZSTREAM_BUFFER_SIZE)
+ return ZSTREAM_BUFFER_SIZE;
+ else if (zstream->in_len > ZSTREAM_BUFFER_MIN_EXTRA)
+ return zstream->in_len;
+ else
+ return ZSTREAM_BUFFER_MIN_EXTRA;
}
-void git_zstream_reset(git_zstream *zstream)
+int git_zstream_get_output_chunk(
+ void *out, size_t *out_len, git_zstream *zstream)
{
- deflateReset(zstream);
+ size_t in_queued, in_used, out_queued;
+
+ /* set up input data */
+ zstream->z.next_in = (Bytef *)zstream->in;
+
+ /* feed as much data to zlib as it can consume, at most UINT_MAX */
+ if (zstream->in_len > UINT_MAX) {
+ zstream->z.avail_in = UINT_MAX;
+ zstream->flush = Z_NO_FLUSH;
+ } else {
+ zstream->z.avail_in = (uInt)zstream->in_len;
+ zstream->flush = Z_FINISH;
+ }
+ in_queued = (size_t)zstream->z.avail_in;
+
+ /* set up output data */
+ zstream->z.next_out = out;
+ zstream->z.avail_out = (uInt)*out_len;
+
+ if ((size_t)zstream->z.avail_out != *out_len)
+ zstream->z.avail_out = UINT_MAX;
+ out_queued = (size_t)zstream->z.avail_out;
+
+ /* compress next chunk */
+ if (zstream->type == GIT_ZSTREAM_INFLATE)
+ zstream->zerr = inflate(&zstream->z, zstream->flush);
+ else
+ zstream->zerr = deflate(&zstream->z, zstream->flush);
+
+ if (zstream_seterr(zstream))
+ return -1;
+
+ in_used = (in_queued - zstream->z.avail_in);
+ zstream->in_len -= in_used;
+ zstream->in += in_used;
+
+ *out_len = (out_queued - zstream->z.avail_out);
+
+ return 0;
}
-void git_zstream_free(git_zstream *zstream)
+int git_zstream_get_output(void *out, size_t *out_len, git_zstream *zstream)
{
- deflateEnd(zstream);
+ size_t out_remain = *out_len;
+
+ if (zstream->in_len && zstream->zerr == Z_STREAM_END) {
+ git_error_set(GIT_ERROR_ZLIB, "zlib input had trailing garbage");
+ return -1;
+ }
+
+ while (out_remain > 0 && zstream->zerr != Z_STREAM_END) {
+ size_t out_written = out_remain;
+
+ if (git_zstream_get_output_chunk(out, &out_written, zstream) < 0)
+ return -1;
+
+ out_remain -= out_written;
+ out = ((char *)out) + out_written;
+ }
+
+ /* either we finished the input or we did not flush the data */
+ GIT_ASSERT(zstream->in_len > 0 || zstream->flush == Z_FINISH);
+
+ /* set out_size to number of bytes actually written to output */
+ *out_len = *out_len - out_remain;
+
+ return 0;
}
-int git_zstream_deflatebuf(git_buf *out, const void *in, size_t in_len)
+static int zstream_buf(git_buf *out, const void *in, size_t in_len, git_zstream_t type)
{
- git_zstream zstream = GIT_ZSTREAM_INIT;
- size_t out_len;
- ssize_t written;
+ git_zstream zs = GIT_ZSTREAM_INIT;
int error = 0;
- if ((error = git_zstream_init(&zstream)) < 0)
+ if ((error = git_zstream_init(&zs, type)) < 0)
+ return error;
+
+ if ((error = git_zstream_set_input(&zs, in, in_len)) < 0)
goto done;
- do {
- if (out->asize - out->size < BUFFER_SIZE)
- git_buf_grow(out, out->asize + BUFFER_SIZE);
+ while (!git_zstream_done(&zs)) {
+ size_t step = git_zstream_suggest_output_len(&zs), written;
+
+ if ((error = git_buf_grow_by(out, step)) < 0)
+ goto done;
- out_len = out->asize - out->size;
+ written = out->asize - out->size;
- if ((written = git_zstream_deflate(out->ptr + out->size, out_len, &zstream, in, in_len)) <= 0)
- break;
+ if ((error = git_zstream_get_output(
+ out->ptr + out->size, &written, &zs)) < 0)
+ goto done;
- in = (char *)in + written;
- in_len -= written;
out->size += written;
- } while (written > 0);
+ }
- if (written < 0)
- error = written;
+ /* NULL terminate for consistency if possible */
+ if (out->size < out->asize)
+ out->ptr[out->size] = '\0';
done:
- git_zstream_free(&zstream);
+ git_zstream_free(&zs);
return error;
}
+
+int git_zstream_deflatebuf(git_buf *out, const void *in, size_t in_len)
+{
+ return zstream_buf(out, in, in_len, GIT_ZSTREAM_DEFLATE);
+}
+
+int git_zstream_inflatebuf(git_buf *out, const void *in, size_t in_len)
+{
+ return zstream_buf(out, in, in_len, GIT_ZSTREAM_INFLATE);
+}
projects / libgit2.git / blobdiff