bulk-checkin: replace fast-import based implementation

This extends the earlier approach to stream a large file directly from the
filesystem to its own packfile, and allows "git add" to send large files
directly into a single pack. Older code used to spawn fast-import, but the
new bulk-checkin API replaces it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Makefile b/Makefile
index 3139c19b10898d735b0d684c269454bc3fd84b68..418dd2e3e6542ba5f7909a3efa324f19a920ab14 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -505,6 +505,7 @@ LIB_H += argv-array.h
 LIB_H += attr.h
 LIB_H += blob.h
 LIB_H += builtin.h
+LIB_H += bulk-checkin.h
 LIB_H += cache.h
 LIB_H += cache-tree.h
 LIB_H += color.h
@@ -591,6 +592,7 @@ LIB_OBJS += base85.o
 LIB_OBJS += bisect.o
 LIB_OBJS += blob.o
 LIB_OBJS += branch.o
+LIB_OBJS += bulk-checkin.o
 LIB_OBJS += bundle.o
 LIB_OBJS += cache-tree.o
 LIB_OBJS += color.o

diff --git a/builtin/add.c b/builtin/add.c
index c59b0c98fefefc413c8330715fffcc83142d5b2d..1c42900ff8c55a94ccfd1d214567d0f64d615412 100644 (file)
--- a/builtin/add.c
+++ b/builtin/add.c
@@ -13,6 +13,7 @@
 #include "diff.h"
 #include "diffcore.h"
 #include "revision.h"
+#include "bulk-checkin.h"
 
 static const char * const builtin_add_usage[] = {
        "git add [options] [--] <filepattern>...",
@@ -458,11 +459,15 @@ int cmd_add(int argc, const char **argv, const char *prefix)
                free(seen);
        }
 
+       plug_bulk_checkin();
+
        exit_status |= add_files_to_cache(prefix, pathspec, flags);
 
        if (add_new_files)
                exit_status |= add_files(&dir, flags);
 
+       unplug_bulk_checkin();
+
  finish:
        if (active_cache_changed) {
                if (write_cache(newfd, active_cache, active_nr) ||

diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index b458b6d3f4f79e8dbcb504c7e6246b59c03db86b..dde913ebb417c1ec200db57de2cc5b49fbcb5984 100644 (file)
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -76,7 +76,7 @@ static struct pack_idx_option pack_idx_opts;
 static const char *base_name;
 static int progress = 1;
 static int window = 10;
-static unsigned long pack_size_limit, pack_size_limit_cfg;
+static unsigned long pack_size_limit;
 static int depth = 50;
 static int delta_search_threads;
 static int pack_to_stdout;
@@ -2009,10 +2009,6 @@ static int git_pack_config(const char *k, const char *v, void *cb)
                            pack_idx_opts.version);
                return 0;
        }
-       if (!strcmp(k, "pack.packsizelimit")) {
-               pack_size_limit_cfg = git_config_ulong(k, v);
-               return 0;
-       }
        return git_default_config(k, v, cb);
 }
 

diff --git a/bulk-checkin.c b/bulk-checkin.c
new file mode 100644 (file)
index 0000000..6b0b6d4
--- /dev/null
+++ b/bulk-checkin.c
@@ -0,0 +1,275 @@
+/*
+ * Copyright (c) 2011, Google Inc.
+ */
+#include "bulk-checkin.h"
+#include "csum-file.h"
+#include "pack.h"
+
+static int pack_compression_level = Z_DEFAULT_COMPRESSION;
+
+static struct bulk_checkin_state {
+       unsigned plugged:1;
+
+       char *pack_tmp_name;
+       struct sha1file *f;
+       off_t offset;
+       struct pack_idx_option pack_idx_opts;
+
+       struct pack_idx_entry **written;
+       uint32_t alloc_written;
+       uint32_t nr_written;
+} state;
+
+static void finish_bulk_checkin(struct bulk_checkin_state *state)
+{
+       unsigned char sha1[20];
+       char packname[PATH_MAX];
+       int i;
+
+       if (!state->f)
+               return;
+
+       if (state->nr_written == 0) {
+               close(state->f->fd);
+               unlink(state->pack_tmp_name);
+               goto clear_exit;
+       } else if (state->nr_written == 1) {
+               sha1close(state->f, sha1, CSUM_FSYNC);
+       } else {
+               int fd = sha1close(state->f, sha1, 0);
+               fixup_pack_header_footer(fd, sha1, state->pack_tmp_name,
+                                        state->nr_written, sha1,
+                                        state->offset);
+               close(fd);
+       }
+
+       sprintf(packname, "%s/pack/pack-", get_object_directory());
+       finish_tmp_packfile(packname, state->pack_tmp_name,
+                           state->written, state->nr_written,
+                           &state->pack_idx_opts, sha1);
+       for (i = 0; i < state->nr_written; i++)
+               free(state->written[i]);
+
+clear_exit:
+       free(state->written);
+       memset(state, 0, sizeof(*state));
+
+       /* Make objects we just wrote available to ourselves */
+       reprepare_packed_git();
+}
+
+static int already_written(struct bulk_checkin_state *state, unsigned char sha1[])
+{
+       int i;
+
+       /* The object may already exist in the repository */
+       if (has_sha1_file(sha1))
+               return 1;
+
+       /* Might want to keep the list sorted */
+       for (i = 0; i < state->nr_written; i++)
+               if (!hashcmp(state->written[i]->sha1, sha1))
+                       return 1;
+
+       /* This is a new object we need to keep */
+       return 0;
+}
+
+/*
+ * Read the contents from fd for size bytes, streaming it to the
+ * packfile in state while updating the hash in ctx. Signal a failure
+ * by returning a negative value when the resulting pack would exceed
+ * the pack size limit and this is not the first object in the pack,
+ * so that the caller can discard what we wrote from the current pack
+ * by truncating it and opening a new one. The caller will then call
+ * us again after rewinding the input fd.
+ *
+ * The already_hashed_to pointer is kept untouched by the caller to
+ * make sure we do not hash the same byte when we are called
+ * again. This way, the caller does not have to checkpoint its hash
+ * status before calling us just in case we ask it to call us again
+ * with a new pack.
+ */
+static int stream_to_pack(struct bulk_checkin_state *state,
+                         git_SHA_CTX *ctx, off_t *already_hashed_to,
+                         int fd, size_t size, enum object_type type,
+                         const char *path, unsigned flags)
+{
+       git_zstream s;
+       unsigned char obuf[16384];
+       unsigned hdrlen;
+       int status = Z_OK;
+       int write_object = (flags & HASH_WRITE_OBJECT);
+       off_t offset = 0;
+
+       memset(&s, 0, sizeof(s));
+       git_deflate_init(&s, pack_compression_level);
+
+       hdrlen = encode_in_pack_object_header(type, size, obuf);
+       s.next_out = obuf + hdrlen;
+       s.avail_out = sizeof(obuf) - hdrlen;
+
+       while (status != Z_STREAM_END) {
+               unsigned char ibuf[16384];
+
+               if (size && !s.avail_in) {
+                       ssize_t rsize = size < sizeof(ibuf) ? size : sizeof(ibuf);
+                       if (xread(fd, ibuf, rsize) != rsize)
+                               die("failed to read %d bytes from '%s'",
+                                   (int)rsize, path);
+                       offset += rsize;
+                       if (*already_hashed_to < offset) {
+                               size_t hsize = offset - *already_hashed_to;
+                               if (rsize < hsize)
+                                       hsize = rsize;
+                               if (hsize)
+                                       git_SHA1_Update(ctx, ibuf, hsize);
+                               *already_hashed_to = offset;
+                       }
+                       s.next_in = ibuf;
+                       s.avail_in = rsize;
+                       size -= rsize;
+               }
+
+               status = git_deflate(&s, size ? 0 : Z_FINISH);
+
+               if (!s.avail_out || status == Z_STREAM_END) {
+                       if (write_object) {
+                               size_t written = s.next_out - obuf;
+
+                               /* would we bust the size limit? */
+                               if (state->nr_written &&
+                                   pack_size_limit_cfg &&
+                                   pack_size_limit_cfg < state->offset + written) {
+                                       git_deflate_abort(&s);
+                                       return -1;
+                               }
+
+                               sha1write(state->f, obuf, written);
+                               state->offset += written;
+                       }
+                       s.next_out = obuf;
+                       s.avail_out = sizeof(obuf);
+               }
+
+               switch (status) {
+               case Z_OK:
+               case Z_BUF_ERROR:
+               case Z_STREAM_END:
+                       continue;
+               default:
+                       die("unexpected deflate failure: %d", status);
+               }
+       }
+       git_deflate_end(&s);
+       return 0;
+}
+
+/* Lazily create backing packfile for the state */
+static void prepare_to_stream(struct bulk_checkin_state *state,
+                             unsigned flags)
+{
+       if (!(flags & HASH_WRITE_OBJECT) || state->f)
+               return;
+
+       state->f = create_tmp_packfile(&state->pack_tmp_name);
+       reset_pack_idx_option(&state->pack_idx_opts);
+
+       /* Pretend we are going to write only one object */
+       state->offset = write_pack_header(state->f, 1);
+       if (!state->offset)
+               die_errno("unable to write pack header");
+}
+
+static int deflate_to_pack(struct bulk_checkin_state *state,
+                          unsigned char result_sha1[],
+                          int fd, size_t size,
+                          enum object_type type, const char *path,
+                          unsigned flags)
+{
+       off_t seekback, already_hashed_to;
+       git_SHA_CTX ctx;
+       unsigned char obuf[16384];
+       unsigned header_len;
+       struct sha1file_checkpoint checkpoint;
+       struct pack_idx_entry *idx = NULL;
+
+       seekback = lseek(fd, 0, SEEK_CUR);
+       if (seekback == (off_t) -1)
+               return error("cannot find the current offset");
+
+       header_len = sprintf((char *)obuf, "%s %" PRIuMAX,
+                            typename(type), (uintmax_t)size) + 1;
+       git_SHA1_Init(&ctx);
+       git_SHA1_Update(&ctx, obuf, header_len);
+
+       /* Note: idx is non-NULL when we are writing */
+       if ((flags & HASH_WRITE_OBJECT) != 0)
+               idx = xcalloc(1, sizeof(*idx));
+
+       already_hashed_to = 0;
+
+       while (1) {
+               prepare_to_stream(state, flags);
+               if (idx) {
+                       sha1file_checkpoint(state->f, &checkpoint);
+                       idx->offset = state->offset;
+                       crc32_begin(state->f);
+               }
+               if (!stream_to_pack(state, &ctx, &already_hashed_to,
+                                   fd, size, type, path, flags))
+                       break;
+               /*
+                * Writing this object to the current pack will make
+                * it too big; we need to truncate it, start a new
+                * pack, and write into it.
+                */
+               if (!idx)
+                       die("BUG: should not happen");
+               sha1file_truncate(state->f, &checkpoint);
+               state->offset = checkpoint.offset;
+               finish_bulk_checkin(state);
+               if (lseek(fd, seekback, SEEK_SET) == (off_t) -1)
+                       return error("cannot seek back");
+       }
+       git_SHA1_Final(result_sha1, &ctx);
+       if (!idx)
+               return 0;
+
+       idx->crc32 = crc32_end(state->f);
+       if (already_written(state, result_sha1)) {
+               sha1file_truncate(state->f, &checkpoint);
+               state->offset = checkpoint.offset;
+               free(idx);
+       } else {
+               hashcpy(idx->sha1, result_sha1);
+               ALLOC_GROW(state->written,
+                          state->nr_written + 1,
+                          state->alloc_written);
+               state->written[state->nr_written++] = idx;
+       }
+       return 0;
+}
+
+int index_bulk_checkin(unsigned char *sha1,
+                      int fd, size_t size, enum object_type type,
+                      const char *path, unsigned flags)
+{
+       int status = deflate_to_pack(&state, sha1, fd, size, type,
+                                    path, flags);
+       if (!state.plugged)
+               finish_bulk_checkin(&state);
+       return status;
+}
+
+void plug_bulk_checkin(void)
+{
+       state.plugged = 1;
+}
+
+void unplug_bulk_checkin(void)
+{
+       state.plugged = 0;
+       if (state.f)
+               finish_bulk_checkin(&state);
+}

diff --git a/bulk-checkin.h b/bulk-checkin.h
new file mode 100644 (file)
index 0000000..4f599f8
--- /dev/null
+++ b/bulk-checkin.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2011, Google Inc.
+ */
+#ifndef BULK_CHECKIN_H
+#define BULK_CHECKIN_H
+
+#include "cache.h"
+
+extern int index_bulk_checkin(unsigned char sha1[],
+                             int fd, size_t size, enum object_type type,
+                             const char *path, unsigned flags);
+
+extern void plug_bulk_checkin(void);
+extern void unplug_bulk_checkin(void);
+
+#endif

diff --git a/cache.h b/cache.h
index 2e6ad3604e4cc6efd60a69407159967a1940e680..4f2086151c8dfa5c8d77625b9403893705287f31 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -35,6 +35,7 @@ int git_inflate(git_zstream *, int flush);
 void git_deflate_init(git_zstream *, int level);
 void git_deflate_init_gzip(git_zstream *, int level);
 void git_deflate_end(git_zstream *);
+int git_deflate_abort(git_zstream *);
 int git_deflate_end_gently(git_zstream *);
 int git_deflate(git_zstream *, int flush);
 unsigned long git_deflate_bound(git_zstream *, unsigned long);
@@ -598,6 +599,7 @@ extern size_t packed_git_window_size;
 extern size_t packed_git_limit;
 extern size_t delta_base_cache_limit;
 extern unsigned long big_file_threshold;
+extern unsigned long pack_size_limit_cfg;
 extern int read_replace_refs;
 extern int fsync_object_files;
 extern int core_preload_index;

diff --git a/config.c b/config.c
index edf9914df6a1a789780c98d53b7b779908bb9141..c736802057f7e723aa1e09205ab1baed3bbfcd4a 100644 (file)
--- a/config.c
+++ b/config.c
@@ -797,6 +797,10 @@ int git_default_config(const char *var, const char *value, void *dummy)
                return 0;
        }
 
+       if (!strcmp(var, "pack.packsizelimit")) {
+               pack_size_limit_cfg = git_config_ulong(var, value);
+               return 0;
+       }
        /* Add other config variables here and to Documentation/config.txt. */
        return 0;
 }

diff --git a/environment.c b/environment.c
index 0bee6a7a88299f8c89eedeee25cece1d3cdafef0..31e42847b185a6f9f51cff60160187f405b01b17 100644 (file)
--- a/environment.c
+++ b/environment.c
@@ -60,6 +60,7 @@ char *notes_ref_name;
 int grafts_replace_parents = 1;
 int core_apply_sparse_checkout;
 struct startup_info *startup_info;
+unsigned long pack_size_limit_cfg;
 
 /* Parallel index stat data preload? */
 int core_preload_index = 0;

diff --git a/sha1_file.c b/sha1_file.c
index 27f3b9b278a97f66f92ca61a2bc39e30f0a70317..c96e366b765f645f3eead72b952d6dc7fe2fef00 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -18,6 +18,7 @@
 #include "refs.h"
 #include "pack-revindex.h"
 #include "sha1-lookup.h"
+#include "bulk-checkin.h"
 
 #ifndef O_NOATIME
 #if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
@@ -2679,10 +2680,8 @@ static int index_core(unsigned char *sha1, int fd, size_t size,
 }
 
 /*
- * This creates one packfile per large blob, because the caller
- * immediately wants the result sha1, and fast-import can report the
- * object name via marks mechanism only by closing the created
- * packfile.
+ * This creates one packfile per large blob unless bulk-checkin
+ * machinery is "plugged".
  *
  * This also bypasses the usual "convert-to-git" dance, and that is on
  * purpose. We could write a streaming version of the converting
@@ -2696,65 +2695,7 @@ static int index_stream(unsigned char *sha1, int fd, size_t size,
                        enum object_type type, const char *path,
                        unsigned flags)
 {
-       struct child_process fast_import;
-       char export_marks[512];
-       const char *argv[] = { "fast-import", "--quiet", export_marks, NULL };
-       char tmpfile[512];
-       char fast_import_cmd[512];
-       char buf[512];
-       int len, tmpfd;
-
-       strcpy(tmpfile, git_path("hashstream_XXXXXX"));
-       tmpfd = git_mkstemp_mode(tmpfile, 0600);
-       if (tmpfd < 0)
-               die_errno("cannot create tempfile: %s", tmpfile);
-       if (close(tmpfd))
-               die_errno("cannot close tempfile: %s", tmpfile);
-       sprintf(export_marks, "--export-marks=%s", tmpfile);
-
-       memset(&fast_import, 0, sizeof(fast_import));
-       fast_import.in = -1;
-       fast_import.argv = argv;
-       fast_import.git_cmd = 1;
-       if (start_command(&fast_import))
-               die_errno("index-stream: git fast-import failed");
-
-       len = sprintf(fast_import_cmd, "blob\nmark :1\ndata %lu\n",
-                     (unsigned long) size);
-       write_or_whine(fast_import.in, fast_import_cmd, len,
-                      "index-stream: feeding fast-import");
-       while (size) {
-               char buf[10240];
-               size_t sz = size < sizeof(buf) ? size : sizeof(buf);
-               ssize_t actual;
-
-               actual = read_in_full(fd, buf, sz);
-               if (actual < 0)
-                       die_errno("index-stream: reading input");
-               if (write_in_full(fast_import.in, buf, actual) != actual)
-                       die_errno("index-stream: feeding fast-import");
-               size -= actual;
-       }
-       if (close(fast_import.in))
-               die_errno("index-stream: closing fast-import");
-       if (finish_command(&fast_import))
-               die_errno("index-stream: finishing fast-import");
-
-       tmpfd = open(tmpfile, O_RDONLY);
-       if (tmpfd < 0)
-               die_errno("index-stream: cannot open fast-import mark");
-       len = read(tmpfd, buf, sizeof(buf));
-       if (len < 0)
-               die_errno("index-stream: reading fast-import mark");
-       if (close(tmpfd) < 0)
-               die_errno("index-stream: closing fast-import mark");
-       if (unlink(tmpfile))
-               die_errno("index-stream: unlinking fast-import mark");
-       if (len != 44 ||
-           memcmp(":1 ", buf, 3) ||
-           get_sha1_hex(buf + 3, sha1))
-               die_errno("index-stream: unexpected fast-import mark: <%s>", buf);
-       return 0;
+       return index_bulk_checkin(sha1, fd, size, type, path, flags);
 }
 
 int index_fd(unsigned char *sha1, int fd, struct stat *st,

diff --git a/t/t1050-large.sh b/t/t1050-large.sh
index deba111bd7c2d26f3bd38dbfa086cec209f81874..29d6024b7f1b55c09cbd7e9ed682a3e745c550d6 100755 (executable)
--- a/t/t1050-large.sh
+++ b/t/t1050-large.sh
@@ -7,21 +7,97 @@ test_description='adding and checking out large blobs'
 
 test_expect_success setup '
        git config core.bigfilethreshold 200k &&
-       echo X | dd of=large bs=1k seek=2000
+       echo X | dd of=large1 bs=1k seek=2000 &&
+       echo X | dd of=large2 bs=1k seek=2000 &&
+       echo X | dd of=large3 bs=1k seek=2000 &&
+       echo Y | dd of=huge bs=1k seek=2500
 '
 
-test_expect_success 'add a large file' '
-       git add large &&
-       # make sure we got a packfile and no loose objects
-       test -f .git/objects/pack/pack-*.pack &&
-       test ! -f .git/objects/??/??????????????????????????????????????
+test_expect_success 'add a large file or two' '
+       git add large1 huge large2 &&
+       # make sure we got a single packfile and no loose objects
+       bad= count=0 idx= &&
+       for p in .git/objects/pack/pack-*.pack
+       do
+               count=$(( $count + 1 ))
+               if test -f "$p" && idx=${p%.pack}.idx && test -f "$idx"
+               then
+                       continue
+               fi
+               bad=t
+       done &&
+       test -z "$bad" &&
+       test $count = 1 &&
+       cnt=$(git show-index <"$idx" | wc -l) &&
+       test $cnt = 2 &&
+       for l in .git/objects/??/??????????????????????????????????????
+       do
+               test -f "$l" || continue
+               bad=t
+       done &&
+       test -z "$bad" &&
+
+       # attempt to add another copy of the same
+       git add large3 &&
+       bad= count=0 &&
+       for p in .git/objects/pack/pack-*.pack
+       do
+               count=$(( $count + 1 ))
+               if test -f "$p" && idx=${p%.pack}.idx && test -f "$idx"
+               then
+                       continue
+               fi
+               bad=t
+       done &&
+       test -z "$bad" &&
+       test $count = 1
 '
 
 test_expect_success 'checkout a large file' '
-       large=$(git rev-parse :large) &&
-       git update-index --add --cacheinfo 100644 $large another &&
+       large1=$(git rev-parse :large1) &&
+       git update-index --add --cacheinfo 100644 $large1 another &&
        git checkout another &&
-       cmp large another ;# this must not be test_cmp
+       cmp large1 another ;# this must not be test_cmp
+'
+
+test_expect_success 'packsize limit' '
+       test_create_repo mid &&
+       (
+               cd mid &&
+               git config core.bigfilethreshold 64k &&
+               git config pack.packsizelimit 256k &&
+
+               # mid1 and mid2 will fit within 256k limit but
+               # appending mid3 will bust the limit and will
+               # result in a separate packfile.
+               test-genrandom "a" $(( 66 * 1024 )) >mid1 &&
+               test-genrandom "b" $(( 80 * 1024 )) >mid2 &&
+               test-genrandom "c" $(( 128 * 1024 )) >mid3 &&
+               git add mid1 mid2 mid3 &&
+
+               count=0
+               for pi in .git/objects/pack/pack-*.idx
+               do
+                       test -f "$pi" && count=$(( $count + 1 ))
+               done &&
+               test $count = 2 &&
+
+               (
+                       git hash-object --stdin <mid1
+                       git hash-object --stdin <mid2
+                       git hash-object --stdin <mid3
+               ) |
+               sort >expect &&
+
+               for pi in .git/objects/pack/pack-*.idx
+               do
+                       git show-index <"$pi"
+               done |
+               sed -e "s/^[0-9]* \([0-9a-f]*\) .*/\1/" |
+               sort >actual &&
+
+               test_cmp expect actual
+       )
 '
 
 test_done

diff --git a/zlib.c b/zlib.c
index 3c63d480c75e9939fb3a047f595b032e9509d681..2b2c0c780e3fca6217c688298053a01aad724505 100644 (file)
--- a/zlib.c
+++ b/zlib.c
@@ -188,13 +188,20 @@ void git_deflate_init_gzip(git_zstream *strm, int level)
            strm->z.msg ? strm->z.msg : "no message");
 }
 
-void git_deflate_end(git_zstream *strm)
+int git_deflate_abort(git_zstream *strm)
 {
        int status;
 
        zlib_pre_call(strm);
        status = deflateEnd(&strm->z);
        zlib_post_call(strm);
+       return status;
+}
+
+void git_deflate_end(git_zstream *strm)
+{
+       int status = git_deflate_abort(strm);
+
        if (status == Z_OK)
                return;
        error("deflateEnd: %s (%s)", zerr_to_string(status),