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-rw-r--r--Makefile2
-rw-r--r--builtin/verify-pack.c4
-rw-r--r--cache.h36
-rw-r--r--convert.c23
-rw-r--r--entry.c112
-rw-r--r--sha1_file.c71
-rw-r--r--streaming.c371
-rw-r--r--streaming.h15
8 files changed, 593 insertions, 41 deletions
diff --git a/Makefile b/Makefile
index e40ac0c7f..f8c72e10a 100644
--- a/Makefile
+++ b/Makefile
@@ -556,6 +556,7 @@ LIB_H += sha1-lookup.h
LIB_H += sideband.h
LIB_H += sigchain.h
LIB_H += strbuf.h
+LIB_H += streaming.h
LIB_H += string-list.h
LIB_H += submodule.h
LIB_H += tag.h
@@ -662,6 +663,7 @@ LIB_OBJS += shallow.o
LIB_OBJS += sideband.o
LIB_OBJS += sigchain.o
LIB_OBJS += strbuf.o
+LIB_OBJS += streaming.o
LIB_OBJS += string-list.o
LIB_OBJS += submodule.o
LIB_OBJS += symlinks.o
diff --git a/builtin/verify-pack.c b/builtin/verify-pack.c
index b6079ae6c..3a919b170 100644
--- a/builtin/verify-pack.c
+++ b/builtin/verify-pack.c
@@ -33,9 +33,9 @@ static void show_pack_info(struct packed_git *p, unsigned int flags)
if (!sha1)
die("internal error pack-check nth-packed-object");
offset = nth_packed_object_offset(p, i);
- type = packed_object_info_detail(p, offset, &size, &store_size,
+ type = typename(packed_object_info_detail(p, offset, &size, &store_size,
&delta_chain_length,
- base_sha1);
+ base_sha1));
if (!stat_only)
printf("%s ", sha1_to_hex(sha1));
if (!delta_chain_length) {
diff --git a/cache.h b/cache.h
index f4bb43ec6..79c9302e2 100644
--- a/cache.h
+++ b/cache.h
@@ -780,6 +780,9 @@ extern int hash_sha1_file(const void *buf, unsigned long len, const char *type,
extern int write_sha1_file(const void *buf, unsigned long len, const char *type, unsigned char *return_sha1);
extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
extern int force_object_loose(const unsigned char *sha1, time_t mtime);
+extern void *map_sha1_file(const unsigned char *sha1, unsigned long *size);
+extern int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz);
+extern int parse_sha1_header(const char *hdr, unsigned long *sizep);
/* global flag to enable extra checks when accessing packed objects */
extern int do_check_packed_object_crc;
@@ -1021,7 +1024,37 @@ extern off_t find_pack_entry_one(const unsigned char *, struct packed_git *);
extern void *unpack_entry(struct packed_git *, off_t, enum object_type *, unsigned long *);
extern unsigned long unpack_object_header_buffer(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep);
extern unsigned long get_size_from_delta(struct packed_git *, struct pack_window **, off_t);
-extern const char *packed_object_info_detail(struct packed_git *, off_t, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
+extern int packed_object_info_detail(struct packed_git *, off_t, unsigned long *, unsigned long *, unsigned int *, unsigned char *);
+extern int unpack_object_header(struct packed_git *, struct pack_window **, off_t *, unsigned long *);
+
+struct object_info {
+ /* Request */
+ unsigned long *sizep;
+
+ /* Response */
+ enum {
+ OI_CACHED,
+ OI_LOOSE,
+ OI_PACKED,
+ OI_DBCACHED
+ } whence;
+ union {
+ /*
+ * struct {
+ * ... Nothing to expose in this case
+ * } cached;
+ * struct {
+ * ... Nothing to expose in this case
+ * } loose;
+ */
+ struct {
+ struct packed_git *pack;
+ off_t offset;
+ unsigned int is_delta;
+ } packed;
+ } u;
+};
+extern int sha1_object_info_extended(const unsigned char *, struct object_info *);
/* Dumb servers support */
extern int update_server_info(int);
@@ -1135,6 +1168,7 @@ extern int convert_to_git(const char *path, const char *src, size_t len,
struct strbuf *dst, enum safe_crlf checksafe);
extern int convert_to_working_tree(const char *path, const char *src, size_t len, struct strbuf *dst);
extern int renormalize_buffer(const char *path, const char *src, size_t len, struct strbuf *dst);
+extern int can_bypass_conversion(const char *path);
/* add */
/*
diff --git a/convert.c b/convert.c
index efc7e07d4..264af1d5b 100644
--- a/convert.c
+++ b/convert.c
@@ -813,3 +813,26 @@ int renormalize_buffer(const char *path, const char *src, size_t len, struct str
}
return ret | convert_to_git(path, src, len, dst, 0);
}
+
+/*
+ * You would be crazy to set CRLF, smuge/clean or ident to
+ * a large binary blob you would want us not to slurp into
+ * the memory!
+ */
+int can_bypass_conversion(const char *path)
+{
+ struct conv_attrs ca;
+ enum crlf_action crlf_action;
+
+ convert_attrs(&ca, path);
+
+ if (ca.ident ||
+ (ca.drv && (ca.drv->smudge || ca.drv->clean)))
+ return 0;
+
+ crlf_action = input_crlf_action(ca.crlf_action, ca.eol_attr);
+ if ((crlf_action == CRLF_BINARY) || (crlf_action == CRLF_INPUT) ||
+ (crlf_action == CRLF_GUESS && auto_crlf == AUTO_CRLF_FALSE))
+ return 1;
+ return 0;
+}
diff --git a/entry.c b/entry.c
index b017167f2..e2dc16c13 100644
--- a/entry.c
+++ b/entry.c
@@ -1,6 +1,7 @@
#include "cache.h"
#include "blob.h"
#include "dir.h"
+#include "streaming.h"
static void create_directories(const char *path, int path_len,
const struct checkout *state)
@@ -91,6 +92,90 @@ static void *read_blob_entry(struct cache_entry *ce, unsigned long *size)
return NULL;
}
+static int open_output_fd(char *path, struct cache_entry *ce, int to_tempfile)
+{
+ int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
+ if (to_tempfile) {
+ strcpy(path, symlink
+ ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
+ return mkstemp(path);
+ } else {
+ return create_file(path, !symlink ? ce->ce_mode : 0666);
+ }
+}
+
+static int fstat_output(int fd, const struct checkout *state, struct stat *st)
+{
+ /* use fstat() only when path == ce->name */
+ if (fstat_is_reliable() &&
+ state->refresh_cache && !state->base_dir_len) {
+ fstat(fd, st);
+ return 1;
+ }
+ return 0;
+}
+
+static int streaming_write_entry(struct cache_entry *ce, char *path,
+ const struct checkout *state, int to_tempfile,
+ int *fstat_done, struct stat *statbuf)
+{
+ struct git_istream *st;
+ enum object_type type;
+ unsigned long sz;
+ int result = -1;
+ ssize_t kept = 0;
+ int fd = -1;
+
+ st = open_istream(ce->sha1, &type, &sz);
+ if (!st)
+ return -1;
+ if (type != OBJ_BLOB)
+ goto close_and_exit;
+
+ fd = open_output_fd(path, ce, to_tempfile);
+ if (fd < 0)
+ goto close_and_exit;
+
+ for (;;) {
+ char buf[1024 * 16];
+ ssize_t wrote, holeto;
+ ssize_t readlen = read_istream(st, buf, sizeof(buf));
+
+ if (!readlen)
+ break;
+ if (sizeof(buf) == readlen) {
+ for (holeto = 0; holeto < readlen; holeto++)
+ if (buf[holeto])
+ break;
+ if (readlen == holeto) {
+ kept += holeto;
+ continue;
+ }
+ }
+
+ if (kept && lseek(fd, kept, SEEK_CUR) == (off_t) -1)
+ goto close_and_exit;
+ else
+ kept = 0;
+ wrote = write_in_full(fd, buf, readlen);
+
+ if (wrote != readlen)
+ goto close_and_exit;
+ }
+ if (kept && (lseek(fd, kept - 1, SEEK_CUR) == (off_t) -1 ||
+ write(fd, "", 1) != 1))
+ goto close_and_exit;
+ *fstat_done = fstat_output(fd, state, statbuf);
+
+close_and_exit:
+ close_istream(st);
+ if (0 <= fd)
+ result = close(fd);
+ if (result && 0 <= fd)
+ unlink(path);
+ return result;
+}
+
static int write_entry(struct cache_entry *ce, char *path, const struct checkout *state, int to_tempfile)
{
unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
@@ -101,6 +186,12 @@ static int write_entry(struct cache_entry *ce, char *path, const struct checkout
size_t wrote, newsize = 0;
struct stat st;
+ if ((ce_mode_s_ifmt == S_IFREG) &&
+ can_bypass_conversion(path) &&
+ !streaming_write_entry(ce, path, state, to_tempfile,
+ &fstat_done, &st))
+ goto finish;
+
switch (ce_mode_s_ifmt) {
case S_IFREG:
case S_IFLNK:
@@ -128,17 +219,7 @@ static int write_entry(struct cache_entry *ce, char *path, const struct checkout
size = newsize;
}
- if (to_tempfile) {
- if (ce_mode_s_ifmt == S_IFREG)
- strcpy(path, ".merge_file_XXXXXX");
- else
- strcpy(path, ".merge_link_XXXXXX");
- fd = mkstemp(path);
- } else if (ce_mode_s_ifmt == S_IFREG) {
- fd = create_file(path, ce->ce_mode);
- } else {
- fd = create_file(path, 0666);
- }
+ fd = open_output_fd(path, ce, to_tempfile);
if (fd < 0) {
free(new);
return error("unable to create file %s (%s)",
@@ -146,12 +227,8 @@ static int write_entry(struct cache_entry *ce, char *path, const struct checkout
}
wrote = write_in_full(fd, new, size);
- /* use fstat() only when path == ce->name */
- if (fstat_is_reliable() &&
- state->refresh_cache && !to_tempfile && !state->base_dir_len) {
- fstat(fd, &st);
- fstat_done = 1;
- }
+ if (!to_tempfile)
+ fstat_done = fstat_output(fd, state, &st);
close(fd);
free(new);
if (wrote != size)
@@ -167,6 +244,7 @@ static int write_entry(struct cache_entry *ce, char *path, const struct checkout
return error("unknown file mode for %s in index", path);
}
+finish:
if (state->refresh_cache) {
if (!fstat_done)
lstat(ce->name, &st);
diff --git a/sha1_file.c b/sha1_file.c
index 064a33040..8a8521799 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -1186,7 +1186,7 @@ static int open_sha1_file(const unsigned char *sha1)
return -1;
}
-static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
+void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
{
void *map;
int fd;
@@ -1245,7 +1245,7 @@ unsigned long unpack_object_header_buffer(const unsigned char *buf,
return used;
}
-static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
+int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
{
unsigned long size, used;
static const char valid_loose_object_type[8] = {
@@ -1342,7 +1342,7 @@ static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size
* too permissive for what we want to check. So do an anal
* object header parse by hand.
*/
-static int parse_sha1_header(const char *hdr, unsigned long *sizep)
+int parse_sha1_header(const char *hdr, unsigned long *sizep)
{
char type[10];
int i;
@@ -1481,7 +1481,7 @@ static off_t get_delta_base(struct packed_git *p,
/* forward declaration for a mutually recursive function */
static int packed_object_info(struct packed_git *p, off_t offset,
- unsigned long *sizep);
+ unsigned long *sizep, int *rtype);
static int packed_delta_info(struct packed_git *p,
struct pack_window **w_curs,
@@ -1495,7 +1495,7 @@ static int packed_delta_info(struct packed_git *p,
base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
if (!base_offset)
return OBJ_BAD;
- type = packed_object_info(p, base_offset, NULL);
+ type = packed_object_info(p, base_offset, NULL, NULL);
if (type <= OBJ_NONE) {
struct revindex_entry *revidx;
const unsigned char *base_sha1;
@@ -1523,10 +1523,10 @@ static int packed_delta_info(struct packed_git *p,
return type;
}
-static int unpack_object_header(struct packed_git *p,
- struct pack_window **w_curs,
- off_t *curpos,
- unsigned long *sizep)
+int unpack_object_header(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t *curpos,
+ unsigned long *sizep)
{
unsigned char *base;
unsigned int left;
@@ -1549,7 +1549,7 @@ static int unpack_object_header(struct packed_git *p,
return type;
}
-const char *packed_object_info_detail(struct packed_git *p,
+int packed_object_info_detail(struct packed_git *p,
off_t obj_offset,
unsigned long *size,
unsigned long *store_size,
@@ -1580,7 +1580,7 @@ const char *packed_object_info_detail(struct packed_git *p,
case OBJ_BLOB:
case OBJ_TAG:
unuse_pack(&w_curs);
- return typename(type);
+ return type;
case OBJ_OFS_DELTA:
obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
if (!obj_offset)
@@ -1605,7 +1605,7 @@ const char *packed_object_info_detail(struct packed_git *p,
}
static int packed_object_info(struct packed_git *p, off_t obj_offset,
- unsigned long *sizep)
+ unsigned long *sizep, int *rtype)
{
struct pack_window *w_curs = NULL;
unsigned long size;
@@ -1613,6 +1613,8 @@ static int packed_object_info(struct packed_git *p, off_t obj_offset,
enum object_type type;
type = unpack_object_header(p, &w_curs, &curpos, &size);
+ if (rtype)
+ *rtype = type; /* representation type */
switch (type) {
case OBJ_OFS_DELTA:
@@ -1695,6 +1697,13 @@ static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
return hash % MAX_DELTA_CACHE;
}
+static int in_delta_base_cache(struct packed_git *p, off_t base_offset)
+{
+ unsigned long hash = pack_entry_hash(p, base_offset);
+ struct delta_base_cache_entry *ent = delta_base_cache + hash;
+ return (ent->data && ent->p == p && ent->base_offset == base_offset);
+}
+
static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
unsigned long *base_size, enum object_type *type, int keep_cache)
{
@@ -2093,24 +2102,28 @@ static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *size
return status;
}
-int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
+/* returns enum object_type or negative */
+int sha1_object_info_extended(const unsigned char *sha1, struct object_info *oi)
{
struct cached_object *co;
struct pack_entry e;
- int status;
+ int status, rtype;
co = find_cached_object(sha1);
if (co) {
- if (sizep)
- *sizep = co->size;
+ if (oi->sizep)
+ *(oi->sizep) = co->size;
+ oi->whence = OI_CACHED;
return co->type;
}
if (!find_pack_entry(sha1, &e)) {
/* Most likely it's a loose object. */
- status = sha1_loose_object_info(sha1, sizep);
- if (status >= 0)
+ status = sha1_loose_object_info(sha1, oi->sizep);
+ if (status >= 0) {
+ oi->whence = OI_LOOSE;
return status;
+ }
/* Not a loose object; someone else may have just packed it. */
reprepare_packed_git();
@@ -2118,15 +2131,31 @@ int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
return status;
}
- status = packed_object_info(e.p, e.offset, sizep);
+ status = packed_object_info(e.p, e.offset, oi->sizep, &rtype);
if (status < 0) {
mark_bad_packed_object(e.p, sha1);
- status = sha1_object_info(sha1, sizep);
+ status = sha1_object_info_extended(sha1, oi);
+ } else if (in_delta_base_cache(e.p, e.offset)) {
+ oi->whence = OI_DBCACHED;
+ } else {
+ oi->whence = OI_PACKED;
+ oi->u.packed.offset = e.offset;
+ oi->u.packed.pack = e.p;
+ oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
+ rtype == OBJ_OFS_DELTA);
}
return status;
}
+int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
+{
+ struct object_info oi;
+
+ oi.sizep = sizep;
+ return sha1_object_info_extended(sha1, &oi);
+}
+
static void *read_packed_sha1(const unsigned char *sha1,
enum object_type *type, unsigned long *size)
{
@@ -2704,7 +2733,7 @@ static int index_stream(unsigned char *sha1, int fd, size_t size,
while (size) {
char buf[10240];
size_t sz = size < sizeof(buf) ? size : sizeof(buf);
- size_t actual;
+ ssize_t actual;
actual = read_in_full(fd, buf, sz);
if (actual < 0)
diff --git a/streaming.c b/streaming.c
new file mode 100644
index 000000000..060292664
--- /dev/null
+++ b/streaming.c
@@ -0,0 +1,371 @@
+/*
+ * Copyright (c) 2011, Google Inc.
+ */
+#include "cache.h"
+#include "streaming.h"
+
+enum input_source {
+ stream_error = -1,
+ incore = 0,
+ loose = 1,
+ pack_non_delta = 2
+};
+
+typedef int (*open_istream_fn)(struct git_istream *,
+ struct object_info *,
+ const unsigned char *,
+ enum object_type *);
+typedef int (*close_istream_fn)(struct git_istream *);
+typedef ssize_t (*read_istream_fn)(struct git_istream *, char *, size_t);
+
+struct stream_vtbl {
+ close_istream_fn close;
+ read_istream_fn read;
+};
+
+#define open_method_decl(name) \
+ int open_istream_ ##name \
+ (struct git_istream *st, struct object_info *oi, \
+ const unsigned char *sha1, \
+ enum object_type *type)
+
+#define close_method_decl(name) \
+ int close_istream_ ##name \
+ (struct git_istream *st)
+
+#define read_method_decl(name) \
+ ssize_t read_istream_ ##name \
+ (struct git_istream *st, char *buf, size_t sz)
+
+/* forward declaration */
+static open_method_decl(incore);
+static open_method_decl(loose);
+static open_method_decl(pack_non_delta);
+
+static open_istream_fn open_istream_tbl[] = {
+ open_istream_incore,
+ open_istream_loose,
+ open_istream_pack_non_delta,
+};
+
+struct git_istream {
+ const struct stream_vtbl *vtbl;
+ unsigned long size; /* inflated size of full object */
+ z_stream z;
+ enum { z_unused, z_used, z_done, z_error } z_state;
+
+ union {
+ struct {
+ char *buf; /* from read_object() */
+ unsigned long read_ptr;
+ } incore;
+
+ struct {
+ void *mapped;
+ unsigned long mapsize;
+ char hdr[32];
+ int hdr_avail;
+ int hdr_used;
+ } loose;
+
+ struct {
+ struct packed_git *pack;
+ off_t pos;
+ } in_pack;
+ } u;
+};
+
+int close_istream(struct git_istream *st)
+{
+ return st->vtbl->close(st);
+}
+
+ssize_t read_istream(struct git_istream *st, char *buf, size_t sz)
+{
+ return st->vtbl->read(st, buf, sz);
+}
+
+static enum input_source istream_source(const unsigned char *sha1,
+ enum object_type *type,
+ struct object_info *oi)
+{
+ unsigned long size;
+ int status;
+
+ oi->sizep = &size;
+ status = sha1_object_info_extended(sha1, oi);
+ if (status < 0)
+ return stream_error;
+ *type = status;
+
+ switch (oi->whence) {
+ case OI_LOOSE:
+ return loose;
+ case OI_PACKED:
+ if (!oi->u.packed.is_delta && big_file_threshold <= size)
+ return pack_non_delta;
+ /* fallthru */
+ default:
+ return incore;
+ }
+}
+
+struct git_istream *open_istream(const unsigned char *sha1,
+ enum object_type *type,
+ unsigned long *size)
+{
+ struct git_istream *st;
+ struct object_info oi;
+ const unsigned char *real = lookup_replace_object(sha1);
+ enum input_source src = istream_source(real, type, &oi);
+
+ if (src < 0)
+ return NULL;
+
+ st = xmalloc(sizeof(*st));
+ if (open_istream_tbl[src](st, &oi, real, type)) {
+ if (open_istream_incore(st, &oi, real, type)) {
+ free(st);
+ return NULL;
+ }
+ }
+ *size = st->size;
+ return st;
+}
+
+
+/*****************************************************************
+ *
+ * Common helpers
+ *
+ *****************************************************************/
+
+static void close_deflated_stream(struct git_istream *st)
+{
+ if (st->z_state == z_used)
+ git_inflate_end(&st->z);
+}
+
+
+/*****************************************************************
+ *
+ * Loose object stream
+ *
+ *****************************************************************/
+
+static read_method_decl(loose)
+{
+ size_t total_read = 0;
+
+ switch (st->z_state) {
+ case z_done:
+ return 0;
+ case z_error:
+ return -1;
+ default:
+ break;
+ }
+
+ if (st->u.loose.hdr_used < st->u.loose.hdr_avail) {
+ size_t to_copy = st->u.loose.hdr_avail - st->u.loose.hdr_used;
+ if (sz < to_copy)
+ to_copy = sz;
+ memcpy(buf, st->u.loose.hdr + st->u.loose.hdr_used, to_copy);
+ st->u.loose.hdr_used += to_copy;
+ total_read += to_copy;
+ }
+
+ while (total_read < sz) {
+ int status;
+
+ st->z.next_out = (unsigned char *)buf + total_read;
+ st->z.avail_out = sz - total_read;
+ status = git_inflate(&st->z, Z_FINISH);
+
+ total_read = st->z.next_out - (unsigned char *)buf;
+
+ if (status == Z_STREAM_END) {
+ git_inflate_end(&st->z);
+ st->z_state = z_done;
+ break;
+ }
+ if (status != Z_OK && status != Z_BUF_ERROR) {
+ git_inflate_end(&st->z);
+ st->z_state = z_error;
+ return -1;
+ }
+ }
+ return total_read;
+}
+
+static close_method_decl(loose)
+{
+ close_deflated_stream(st);
+ munmap(st->u.loose.mapped, st->u.loose.mapsize);
+ return 0;
+}
+
+static struct stream_vtbl loose_vtbl = {
+ close_istream_loose,
+ read_istream_loose,
+};
+
+static open_method_decl(loose)
+{
+ st->u.loose.mapped = map_sha1_file(sha1, &st->u.loose.mapsize);
+ if (!st->u.loose.mapped)
+ return -1;
+ if (unpack_sha1_header(&st->z,
+ st->u.loose.mapped,
+ st->u.loose.mapsize,
+ st->u.loose.hdr,
+ sizeof(st->u.loose.hdr)) < 0) {
+ git_inflate_end(&st->z);
+ munmap(st->u.loose.mapped, st->u.loose.mapsize);
+ return -1;
+ }
+
+ parse_sha1_header(st->u.loose.hdr, &st->size);
+ st->u.loose.hdr_used = strlen(st->u.loose.hdr) + 1;
+ st->u.loose.hdr_avail = st->z.total_out;
+ st->z_state = z_used;
+
+ st->vtbl = &loose_vtbl;
+ return 0;
+}
+
+
+/*****************************************************************
+ *
+ * Non-delta packed object stream
+ *
+ *****************************************************************/
+
+static read_method_decl(pack_non_delta)
+{
+ size_t total_read = 0;
+
+ switch (st->z_state) {
+ case z_unused:
+ memset(&st->z, 0, sizeof(st->z));
+ git_inflate_init(&st->z);
+ st->z_state = z_used;
+ break;
+ case z_done:
+ return 0;
+ case z_error:
+ return -1;
+ case z_used:
+ break;
+ }
+
+ while (total_read < sz) {
+ int status;
+ struct pack_window *window = NULL;
+ unsigned char *mapped;
+
+ mapped = use_pack(st->u.in_pack.pack, &window,
+ st->u.in_pack.pos, &st->z.avail_in);
+
+ st->z.next_out = (unsigned char *)buf + total_read;
+ st->z.avail_out = sz - total_read;
+ st->z.next_in = mapped;
+ status = git_inflate(&st->z, Z_FINISH);
+
+ st->u.in_pack.pos += st->z.next_in - mapped;
+ total_read = st->z.next_out - (unsigned char *)buf;
+ unuse_pack(&window);
+
+ if (status == Z_STREAM_END) {
+ git_inflate_end(&st->z);
+ st->z_state = z_done;
+ break;
+ }
+ if (status != Z_OK && status != Z_BUF_ERROR) {
+ git_inflate_end(&st->z);
+ st->z_state = z_error;
+ return -1;
+ }
+ }
+ return total_read;
+}
+
+static close_method_decl(pack_non_delta)
+{
+ close_deflated_stream(st);
+ return 0;
+}
+
+static struct stream_vtbl pack_non_delta_vtbl = {
+ close_istream_pack_non_delta,
+ read_istream_pack_non_delta,
+};
+
+static open_method_decl(pack_non_delta)
+{
+ struct pack_window *window;
+ enum object_type in_pack_type;
+
+ st->u.in_pack.pack = oi->u.packed.pack;
+ st->u.in_pack.pos = oi->u.packed.offset;
+ window = NULL;
+
+ in_pack_type = unpack_object_header(st->u.in_pack.pack,
+ &window,
+ &st->u.in_pack.pos,
+ &st->size);
+ unuse_pack(&window);
+ switch (in_pack_type) {
+ default:
+ return -1; /* we do not do deltas for now */
+ case OBJ_COMMIT:
+ case OBJ_TREE:
+ case OBJ_BLOB:
+ case OBJ_TAG:
+ break;
+ }
+ st->z_state = z_unused;
+ st->vtbl = &pack_non_delta_vtbl;
+ return 0;
+}
+
+
+/*****************************************************************
+ *
+ * In-core stream
+ *
+ *****************************************************************/
+
+static close_method_decl(incore)
+{
+ free(st->u.incore.buf);
+ return 0;
+}
+
+static read_method_decl(incore)
+{
+ size_t read_size = sz;
+ size_t remainder = st->size - st->u.incore.read_ptr;
+
+ if (remainder <= read_size)
+ read_size = remainder;
+ if (read_size) {
+ memcpy(buf, st->u.incore.buf + st->u.incore.read_ptr, read_size);
+ st->u.incore.read_ptr += read_size;
+ }
+ return read_size;
+}
+
+static struct stream_vtbl incore_vtbl = {
+ close_istream_incore,
+ read_istream_incore,
+};
+
+static open_method_decl(incore)
+{
+ st->u.incore.buf = read_sha1_file_extended(sha1, type, &st->size, 0);
+ st->u.incore.read_ptr = 0;
+ st->vtbl = &incore_vtbl;
+
+ return st->u.incore.buf ? 0 : -1;
+}
diff --git a/streaming.h b/streaming.h
new file mode 100644
index 000000000..18cbe68ac
--- /dev/null
+++ b/streaming.h
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2011, Google Inc.
+ */
+#ifndef STREAMING_H
+#define STREAMING_H 1
+#include "cache.h"
+
+/* opaque */
+struct git_istream;
+
+extern struct git_istream *open_istream(const unsigned char *, enum object_type *, unsigned long *);
+extern int close_istream(struct git_istream *);
+extern ssize_t read_istream(struct git_istream *, char *, size_t);
+
+#endif /* STREAMING_H */