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index c4d58da4e9050c6330ff145914cc379f0600f703..3c63d480c75e9939fb3a047f595b032e9509d681 100644 (file)
--- a/zlib.c
+++ b/zlib.c
*/
#include "cache.h"
-void git_inflate_init(z_streamp strm)
+static const char *zerr_to_string(int status)
{
- const char *err;
+ switch (status) {
+ case Z_MEM_ERROR:
+ return "out of memory";
+ case Z_VERSION_ERROR:
+ return "wrong version";
+ case Z_NEED_DICT:
+ return "needs dictionary";
+ case Z_DATA_ERROR:
+ return "data stream error";
+ case Z_STREAM_ERROR:
+ return "stream consistency error";
+ default:
+ return "unknown error";
+ }
+}
- switch (inflateInit(strm)) {
- case Z_OK:
+/*
+ * avail_in and avail_out in zlib are counted in uInt, which typically
+ * limits the size of the buffer we can use to 4GB when interacting
+ * with zlib in a single call to inflate/deflate.
+ */
+/* #define ZLIB_BUF_MAX ((uInt)-1) */
+#define ZLIB_BUF_MAX ((uInt) 1024 * 1024 * 1024) /* 1GB */
+static inline uInt zlib_buf_cap(unsigned long len)
+{
+ return (ZLIB_BUF_MAX < len) ? ZLIB_BUF_MAX : len;
+}
+
+static void zlib_pre_call(git_zstream *s)
+{
+ s->z.next_in = s->next_in;
+ s->z.next_out = s->next_out;
+ s->z.total_in = s->total_in;
+ s->z.total_out = s->total_out;
+ s->z.avail_in = zlib_buf_cap(s->avail_in);
+ s->z.avail_out = zlib_buf_cap(s->avail_out);
+}
+
+static void zlib_post_call(git_zstream *s)
+{
+ unsigned long bytes_consumed;
+ unsigned long bytes_produced;
+
+ bytes_consumed = s->z.next_in - s->next_in;
+ bytes_produced = s->z.next_out - s->next_out;
+ if (s->z.total_out != s->total_out + bytes_produced)
+ die("BUG: total_out mismatch");
+ if (s->z.total_in != s->total_in + bytes_consumed)
+ die("BUG: total_in mismatch");
+
+ s->total_out = s->z.total_out;
+ s->total_in = s->z.total_in;
+ s->next_in = s->z.next_in;
+ s->next_out = s->z.next_out;
+ s->avail_in -= bytes_consumed;
+ s->avail_out -= bytes_produced;
+}
+
+void git_inflate_init(git_zstream *strm)
+{
+ int status;
+
+ zlib_pre_call(strm);
+ status = inflateInit(&strm->z);
+ zlib_post_call(strm);
+ if (status == Z_OK)
return;
+ die("inflateInit: %s (%s)", zerr_to_string(status),
+ strm->z.msg ? strm->z.msg : "no message");
+}
- case Z_MEM_ERROR:
- err = "out of memory";
- break;
- case Z_VERSION_ERROR:
- err = "wrong version";
+void git_inflate_init_gzip_only(git_zstream *strm)
+{
+ /*
+ * Use default 15 bits, +16 is to accept only gzip and to
+ * yield Z_DATA_ERROR when fed zlib format.
+ */
+ const int windowBits = 15 + 16;
+ int status;
+
+ zlib_pre_call(strm);
+ status = inflateInit2(&strm->z, windowBits);
+ zlib_post_call(strm);
+ if (status == Z_OK)
+ return;
+ die("inflateInit2: %s (%s)", zerr_to_string(status),
+ strm->z.msg ? strm->z.msg : "no message");
+}
+
+void git_inflate_end(git_zstream *strm)
+{
+ int status;
+
+ zlib_pre_call(strm);
+ status = inflateEnd(&strm->z);
+ zlib_post_call(strm);
+ if (status == Z_OK)
+ return;
+ error("inflateEnd: %s (%s)", zerr_to_string(status),
+ strm->z.msg ? strm->z.msg : "no message");
+}
+
+int git_inflate(git_zstream *strm, int flush)
+{
+ int status;
+
+ for (;;) {
+ zlib_pre_call(strm);
+ /* Never say Z_FINISH unless we are feeding everything */
+ status = inflate(&strm->z,
+ (strm->z.avail_in != strm->avail_in)
+ ? 0 : flush);
+ if (status == Z_MEM_ERROR)
+ die("inflate: out of memory");
+ zlib_post_call(strm);
+
+ /*
+ * Let zlib work another round, while we can still
+ * make progress.
+ */
+ if ((strm->avail_out && !strm->z.avail_out) &&
+ (status == Z_OK || status == Z_BUF_ERROR))
+ continue;
break;
+ }
+
+ switch (status) {
+ /* Z_BUF_ERROR: normal, needs more space in the output buffer */
+ case Z_BUF_ERROR:
+ case Z_OK:
+ case Z_STREAM_END:
+ return status;
default:
- err = "error";
+ break;
}
- die("inflateInit: %s (%s)", err, strm->msg ? strm->msg : "no message");
+ error("inflate: %s (%s)", zerr_to_string(status),
+ strm->z.msg ? strm->z.msg : "no message");
+ return status;
}
-void git_inflate_end(z_streamp strm)
+#if defined(NO_DEFLATE_BOUND) || ZLIB_VERNUM < 0x1200
+#define deflateBound(c,s) ((s) + (((s) + 7) >> 3) + (((s) + 63) >> 6) + 11)
+#endif
+
+unsigned long git_deflate_bound(git_zstream *strm, unsigned long size)
{
- if (inflateEnd(strm) != Z_OK)
- error("inflateEnd: %s", strm->msg ? strm->msg : "failed");
+ return deflateBound(&strm->z, size);
}
-int git_inflate(z_streamp strm, int flush)
+void git_deflate_init(git_zstream *strm, int level)
{
- int ret = inflate(strm, flush);
- const char *err;
+ int status;
- switch (ret) {
- /* Out of memory is fatal. */
- case Z_MEM_ERROR:
- die("inflate: out of memory");
+ zlib_pre_call(strm);
+ status = deflateInit(&strm->z, level);
+ zlib_post_call(strm);
+ if (status == Z_OK)
+ return;
+ die("deflateInit: %s (%s)", zerr_to_string(status),
+ strm->z.msg ? strm->z.msg : "no message");
+}
- /* Data corruption errors: we may want to recover from them (fsck) */
- case Z_NEED_DICT:
- err = "needs dictionary"; break;
- case Z_DATA_ERROR:
- err = "data stream error"; break;
- case Z_STREAM_ERROR:
- err = "stream consistency error"; break;
- default:
- err = "unknown error"; break;
+void git_deflate_init_gzip(git_zstream *strm, int level)
+{
+ /*
+ * Use default 15 bits, +16 is to generate gzip header/trailer
+ * instead of the zlib wrapper.
+ */
+ const int windowBits = 15 + 16;
+ int status;
+ zlib_pre_call(strm);
+ status = deflateInit2(&strm->z, level,
+ Z_DEFLATED, windowBits,
+ 8, Z_DEFAULT_STRATEGY);
+ zlib_post_call(strm);
+ if (status == Z_OK)
+ return;
+ die("deflateInit2: %s (%s)", zerr_to_string(status),
+ strm->z.msg ? strm->z.msg : "no message");
+}
+
+void git_deflate_end(git_zstream *strm)
+{
+ int status;
+
+ zlib_pre_call(strm);
+ status = deflateEnd(&strm->z);
+ zlib_post_call(strm);
+ if (status == Z_OK)
+ return;
+ error("deflateEnd: %s (%s)", zerr_to_string(status),
+ strm->z.msg ? strm->z.msg : "no message");
+}
+
+int git_deflate_end_gently(git_zstream *strm)
+{
+ int status;
+
+ zlib_pre_call(strm);
+ status = deflateEnd(&strm->z);
+ zlib_post_call(strm);
+ return status;
+}
+
+int git_deflate(git_zstream *strm, int flush)
+{
+ int status;
+
+ for (;;) {
+ zlib_pre_call(strm);
+
+ /* Never say Z_FINISH unless we are feeding everything */
+ status = deflate(&strm->z,
+ (strm->z.avail_in != strm->avail_in)
+ ? 0 : flush);
+ if (status == Z_MEM_ERROR)
+ die("deflate: out of memory");
+ zlib_post_call(strm);
+
+ /*
+ * Let zlib work another round, while we can still
+ * make progress.
+ */
+ if ((strm->avail_out && !strm->z.avail_out) &&
+ (status == Z_OK || status == Z_BUF_ERROR))
+ continue;
+ break;
+ }
+
+ switch (status) {
/* Z_BUF_ERROR: normal, needs more space in the output buffer */
case Z_BUF_ERROR:
case Z_OK:
case Z_STREAM_END:
- return ret;
+ return status;
+ default:
+ break;
}
- error("inflate: %s (%s)", err, strm->msg ? strm->msg : "no message");
- return ret;
+ error("deflate: %s (%s)", zerr_to_string(status),
+ strm->z.msg ? strm->z.msg : "no message");
+ return status;
}