Merge branch 'rs/pcre2-utf'
[git/debian.git] / bulk-checkin.c
blob8785b2ac80699255ae8abd0801922ba025235309
1 /*
2 * Copyright (c) 2011, Google Inc.
3 */
4 #include "cache.h"
5 #include "bulk-checkin.h"
6 #include "repository.h"
7 #include "csum-file.h"
8 #include "pack.h"
9 #include "strbuf.h"
10 #include "packfile.h"
11 #include "object-store.h"
13 static struct bulk_checkin_state {
14 unsigned plugged:1;
16 char *pack_tmp_name;
17 struct hashfile *f;
18 off_t offset;
19 struct pack_idx_option pack_idx_opts;
21 struct pack_idx_entry **written;
22 uint32_t alloc_written;
23 uint32_t nr_written;
24 } state;
26 static void finish_tmp_packfile(struct strbuf *basename,
27 const char *pack_tmp_name,
28 struct pack_idx_entry **written_list,
29 uint32_t nr_written,
30 struct pack_idx_option *pack_idx_opts,
31 unsigned char hash[])
33 char *idx_tmp_name = NULL;
35 stage_tmp_packfiles(basename, pack_tmp_name, written_list, nr_written,
36 pack_idx_opts, hash, &idx_tmp_name);
37 rename_tmp_packfile_idx(basename, &idx_tmp_name);
39 free(idx_tmp_name);
42 static void finish_bulk_checkin(struct bulk_checkin_state *state)
44 unsigned char hash[GIT_MAX_RAWSZ];
45 struct strbuf packname = STRBUF_INIT;
46 int i;
48 if (!state->f)
49 return;
51 if (state->nr_written == 0) {
52 close(state->f->fd);
53 unlink(state->pack_tmp_name);
54 goto clear_exit;
55 } else if (state->nr_written == 1) {
56 finalize_hashfile(state->f, hash, CSUM_HASH_IN_STREAM | CSUM_FSYNC | CSUM_CLOSE);
57 } else {
58 int fd = finalize_hashfile(state->f, hash, 0);
59 fixup_pack_header_footer(fd, hash, state->pack_tmp_name,
60 state->nr_written, hash,
61 state->offset);
62 close(fd);
65 strbuf_addf(&packname, "%s/pack/pack-%s.", get_object_directory(),
66 hash_to_hex(hash));
67 finish_tmp_packfile(&packname, state->pack_tmp_name,
68 state->written, state->nr_written,
69 &state->pack_idx_opts, hash);
70 for (i = 0; i < state->nr_written; i++)
71 free(state->written[i]);
73 clear_exit:
74 free(state->written);
75 memset(state, 0, sizeof(*state));
77 strbuf_release(&packname);
78 /* Make objects we just wrote available to ourselves */
79 reprepare_packed_git(the_repository);
82 static int already_written(struct bulk_checkin_state *state, struct object_id *oid)
84 int i;
86 /* The object may already exist in the repository */
87 if (has_object_file(oid))
88 return 1;
90 /* Might want to keep the list sorted */
91 for (i = 0; i < state->nr_written; i++)
92 if (oideq(&state->written[i]->oid, oid))
93 return 1;
95 /* This is a new object we need to keep */
96 return 0;
100 * Read the contents from fd for size bytes, streaming it to the
101 * packfile in state while updating the hash in ctx. Signal a failure
102 * by returning a negative value when the resulting pack would exceed
103 * the pack size limit and this is not the first object in the pack,
104 * so that the caller can discard what we wrote from the current pack
105 * by truncating it and opening a new one. The caller will then call
106 * us again after rewinding the input fd.
108 * The already_hashed_to pointer is kept untouched by the caller to
109 * make sure we do not hash the same byte when we are called
110 * again. This way, the caller does not have to checkpoint its hash
111 * status before calling us just in case we ask it to call us again
112 * with a new pack.
114 static int stream_to_pack(struct bulk_checkin_state *state,
115 git_hash_ctx *ctx, off_t *already_hashed_to,
116 int fd, size_t size, enum object_type type,
117 const char *path, unsigned flags)
119 git_zstream s;
120 unsigned char ibuf[16384];
121 unsigned char obuf[16384];
122 unsigned hdrlen;
123 int status = Z_OK;
124 int write_object = (flags & HASH_WRITE_OBJECT);
125 off_t offset = 0;
127 git_deflate_init(&s, pack_compression_level);
129 hdrlen = encode_in_pack_object_header(obuf, sizeof(obuf), type, size);
130 s.next_out = obuf + hdrlen;
131 s.avail_out = sizeof(obuf) - hdrlen;
133 while (status != Z_STREAM_END) {
134 if (size && !s.avail_in) {
135 ssize_t rsize = size < sizeof(ibuf) ? size : sizeof(ibuf);
136 ssize_t read_result = read_in_full(fd, ibuf, rsize);
137 if (read_result < 0)
138 die_errno("failed to read from '%s'", path);
139 if (read_result != rsize)
140 die("failed to read %d bytes from '%s'",
141 (int)rsize, path);
142 offset += rsize;
143 if (*already_hashed_to < offset) {
144 size_t hsize = offset - *already_hashed_to;
145 if (rsize < hsize)
146 hsize = rsize;
147 if (hsize)
148 the_hash_algo->update_fn(ctx, ibuf, hsize);
149 *already_hashed_to = offset;
151 s.next_in = ibuf;
152 s.avail_in = rsize;
153 size -= rsize;
156 status = git_deflate(&s, size ? 0 : Z_FINISH);
158 if (!s.avail_out || status == Z_STREAM_END) {
159 if (write_object) {
160 size_t written = s.next_out - obuf;
162 /* would we bust the size limit? */
163 if (state->nr_written &&
164 pack_size_limit_cfg &&
165 pack_size_limit_cfg < state->offset + written) {
166 git_deflate_abort(&s);
167 return -1;
170 hashwrite(state->f, obuf, written);
171 state->offset += written;
173 s.next_out = obuf;
174 s.avail_out = sizeof(obuf);
177 switch (status) {
178 case Z_OK:
179 case Z_BUF_ERROR:
180 case Z_STREAM_END:
181 continue;
182 default:
183 die("unexpected deflate failure: %d", status);
186 git_deflate_end(&s);
187 return 0;
190 /* Lazily create backing packfile for the state */
191 static void prepare_to_stream(struct bulk_checkin_state *state,
192 unsigned flags)
194 if (!(flags & HASH_WRITE_OBJECT) || state->f)
195 return;
197 state->f = create_tmp_packfile(&state->pack_tmp_name);
198 reset_pack_idx_option(&state->pack_idx_opts);
200 /* Pretend we are going to write only one object */
201 state->offset = write_pack_header(state->f, 1);
202 if (!state->offset)
203 die_errno("unable to write pack header");
206 static int deflate_to_pack(struct bulk_checkin_state *state,
207 struct object_id *result_oid,
208 int fd, size_t size,
209 enum object_type type, const char *path,
210 unsigned flags)
212 off_t seekback, already_hashed_to;
213 git_hash_ctx ctx;
214 unsigned char obuf[16384];
215 unsigned header_len;
216 struct hashfile_checkpoint checkpoint = {0};
217 struct pack_idx_entry *idx = NULL;
219 seekback = lseek(fd, 0, SEEK_CUR);
220 if (seekback == (off_t) -1)
221 return error("cannot find the current offset");
223 header_len = xsnprintf((char *)obuf, sizeof(obuf), "%s %" PRIuMAX,
224 type_name(type), (uintmax_t)size) + 1;
225 the_hash_algo->init_fn(&ctx);
226 the_hash_algo->update_fn(&ctx, obuf, header_len);
228 /* Note: idx is non-NULL when we are writing */
229 if ((flags & HASH_WRITE_OBJECT) != 0)
230 CALLOC_ARRAY(idx, 1);
232 already_hashed_to = 0;
234 while (1) {
235 prepare_to_stream(state, flags);
236 if (idx) {
237 hashfile_checkpoint(state->f, &checkpoint);
238 idx->offset = state->offset;
239 crc32_begin(state->f);
241 if (!stream_to_pack(state, &ctx, &already_hashed_to,
242 fd, size, type, path, flags))
243 break;
245 * Writing this object to the current pack will make
246 * it too big; we need to truncate it, start a new
247 * pack, and write into it.
249 if (!idx)
250 BUG("should not happen");
251 hashfile_truncate(state->f, &checkpoint);
252 state->offset = checkpoint.offset;
253 finish_bulk_checkin(state);
254 if (lseek(fd, seekback, SEEK_SET) == (off_t) -1)
255 return error("cannot seek back");
257 the_hash_algo->final_oid_fn(result_oid, &ctx);
258 if (!idx)
259 return 0;
261 idx->crc32 = crc32_end(state->f);
262 if (already_written(state, result_oid)) {
263 hashfile_truncate(state->f, &checkpoint);
264 state->offset = checkpoint.offset;
265 free(idx);
266 } else {
267 oidcpy(&idx->oid, result_oid);
268 ALLOC_GROW(state->written,
269 state->nr_written + 1,
270 state->alloc_written);
271 state->written[state->nr_written++] = idx;
273 return 0;
276 int index_bulk_checkin(struct object_id *oid,
277 int fd, size_t size, enum object_type type,
278 const char *path, unsigned flags)
280 int status = deflate_to_pack(&state, oid, fd, size, type,
281 path, flags);
282 if (!state.plugged)
283 finish_bulk_checkin(&state);
284 return status;
287 void plug_bulk_checkin(void)
289 state.plugged = 1;
292 void unplug_bulk_checkin(void)
294 state.plugged = 0;
295 if (state.f)
296 finish_bulk_checkin(&state);