branch: add test for -m renaming multiple config sections
[git.git] / bulk-checkin.c
blob5be7ce5c730f128903ed226c45834dcb2c5c3214
1 /*
2 * Copyright (c) 2011, Google Inc.
3 */
4 #include "cache.h"
5 #include "bulk-checkin.h"
6 #include "csum-file.h"
7 #include "pack.h"
8 #include "strbuf.h"
10 static struct bulk_checkin_state {
11 unsigned plugged:1;
13 char *pack_tmp_name;
14 struct sha1file *f;
15 off_t offset;
16 struct pack_idx_option pack_idx_opts;
18 struct pack_idx_entry **written;
19 uint32_t alloc_written;
20 uint32_t nr_written;
21 } state;
23 static void finish_bulk_checkin(struct bulk_checkin_state *state)
25 struct object_id oid;
26 struct strbuf packname = STRBUF_INIT;
27 int i;
29 if (!state->f)
30 return;
32 if (state->nr_written == 0) {
33 close(state->f->fd);
34 unlink(state->pack_tmp_name);
35 goto clear_exit;
36 } else if (state->nr_written == 1) {
37 sha1close(state->f, oid.hash, CSUM_FSYNC);
38 } else {
39 int fd = sha1close(state->f, oid.hash, 0);
40 fixup_pack_header_footer(fd, oid.hash, state->pack_tmp_name,
41 state->nr_written, oid.hash,
42 state->offset);
43 close(fd);
46 strbuf_addf(&packname, "%s/pack/pack-", get_object_directory());
47 finish_tmp_packfile(&packname, state->pack_tmp_name,
48 state->written, state->nr_written,
49 &state->pack_idx_opts, oid.hash);
50 for (i = 0; i < state->nr_written; i++)
51 free(state->written[i]);
53 clear_exit:
54 free(state->written);
55 memset(state, 0, sizeof(*state));
57 strbuf_release(&packname);
58 /* Make objects we just wrote available to ourselves */
59 reprepare_packed_git();
62 static int already_written(struct bulk_checkin_state *state, unsigned char sha1[])
64 int i;
66 /* The object may already exist in the repository */
67 if (has_sha1_file(sha1))
68 return 1;
70 /* Might want to keep the list sorted */
71 for (i = 0; i < state->nr_written; i++)
72 if (!hashcmp(state->written[i]->oid.hash, sha1))
73 return 1;
75 /* This is a new object we need to keep */
76 return 0;
80 * Read the contents from fd for size bytes, streaming it to the
81 * packfile in state while updating the hash in ctx. Signal a failure
82 * by returning a negative value when the resulting pack would exceed
83 * the pack size limit and this is not the first object in the pack,
84 * so that the caller can discard what we wrote from the current pack
85 * by truncating it and opening a new one. The caller will then call
86 * us again after rewinding the input fd.
88 * The already_hashed_to pointer is kept untouched by the caller to
89 * make sure we do not hash the same byte when we are called
90 * again. This way, the caller does not have to checkpoint its hash
91 * status before calling us just in case we ask it to call us again
92 * with a new pack.
94 static int stream_to_pack(struct bulk_checkin_state *state,
95 git_SHA_CTX *ctx, off_t *already_hashed_to,
96 int fd, size_t size, enum object_type type,
97 const char *path, unsigned flags)
99 git_zstream s;
100 unsigned char obuf[16384];
101 unsigned hdrlen;
102 int status = Z_OK;
103 int write_object = (flags & HASH_WRITE_OBJECT);
104 off_t offset = 0;
106 git_deflate_init(&s, pack_compression_level);
108 hdrlen = encode_in_pack_object_header(obuf, sizeof(obuf), type, size);
109 s.next_out = obuf + hdrlen;
110 s.avail_out = sizeof(obuf) - hdrlen;
112 while (status != Z_STREAM_END) {
113 unsigned char ibuf[16384];
115 if (size && !s.avail_in) {
116 ssize_t rsize = size < sizeof(ibuf) ? size : sizeof(ibuf);
117 if (read_in_full(fd, ibuf, rsize) != rsize)
118 die("failed to read %d bytes from '%s'",
119 (int)rsize, path);
120 offset += rsize;
121 if (*already_hashed_to < offset) {
122 size_t hsize = offset - *already_hashed_to;
123 if (rsize < hsize)
124 hsize = rsize;
125 if (hsize)
126 git_SHA1_Update(ctx, ibuf, hsize);
127 *already_hashed_to = offset;
129 s.next_in = ibuf;
130 s.avail_in = rsize;
131 size -= rsize;
134 status = git_deflate(&s, size ? 0 : Z_FINISH);
136 if (!s.avail_out || status == Z_STREAM_END) {
137 if (write_object) {
138 size_t written = s.next_out - obuf;
140 /* would we bust the size limit? */
141 if (state->nr_written &&
142 pack_size_limit_cfg &&
143 pack_size_limit_cfg < state->offset + written) {
144 git_deflate_abort(&s);
145 return -1;
148 sha1write(state->f, obuf, written);
149 state->offset += written;
151 s.next_out = obuf;
152 s.avail_out = sizeof(obuf);
155 switch (status) {
156 case Z_OK:
157 case Z_BUF_ERROR:
158 case Z_STREAM_END:
159 continue;
160 default:
161 die("unexpected deflate failure: %d", status);
164 git_deflate_end(&s);
165 return 0;
168 /* Lazily create backing packfile for the state */
169 static void prepare_to_stream(struct bulk_checkin_state *state,
170 unsigned flags)
172 if (!(flags & HASH_WRITE_OBJECT) || state->f)
173 return;
175 state->f = create_tmp_packfile(&state->pack_tmp_name);
176 reset_pack_idx_option(&state->pack_idx_opts);
178 /* Pretend we are going to write only one object */
179 state->offset = write_pack_header(state->f, 1);
180 if (!state->offset)
181 die_errno("unable to write pack header");
184 static int deflate_to_pack(struct bulk_checkin_state *state,
185 unsigned char result_sha1[],
186 int fd, size_t size,
187 enum object_type type, const char *path,
188 unsigned flags)
190 off_t seekback, already_hashed_to;
191 git_SHA_CTX ctx;
192 unsigned char obuf[16384];
193 unsigned header_len;
194 struct sha1file_checkpoint checkpoint;
195 struct pack_idx_entry *idx = NULL;
197 seekback = lseek(fd, 0, SEEK_CUR);
198 if (seekback == (off_t) -1)
199 return error("cannot find the current offset");
201 header_len = xsnprintf((char *)obuf, sizeof(obuf), "%s %" PRIuMAX,
202 typename(type), (uintmax_t)size) + 1;
203 git_SHA1_Init(&ctx);
204 git_SHA1_Update(&ctx, obuf, header_len);
206 /* Note: idx is non-NULL when we are writing */
207 if ((flags & HASH_WRITE_OBJECT) != 0)
208 idx = xcalloc(1, sizeof(*idx));
210 already_hashed_to = 0;
212 while (1) {
213 prepare_to_stream(state, flags);
214 if (idx) {
215 sha1file_checkpoint(state->f, &checkpoint);
216 idx->offset = state->offset;
217 crc32_begin(state->f);
219 if (!stream_to_pack(state, &ctx, &already_hashed_to,
220 fd, size, type, path, flags))
221 break;
223 * Writing this object to the current pack will make
224 * it too big; we need to truncate it, start a new
225 * pack, and write into it.
227 if (!idx)
228 die("BUG: should not happen");
229 sha1file_truncate(state->f, &checkpoint);
230 state->offset = checkpoint.offset;
231 finish_bulk_checkin(state);
232 if (lseek(fd, seekback, SEEK_SET) == (off_t) -1)
233 return error("cannot seek back");
235 git_SHA1_Final(result_sha1, &ctx);
236 if (!idx)
237 return 0;
239 idx->crc32 = crc32_end(state->f);
240 if (already_written(state, result_sha1)) {
241 sha1file_truncate(state->f, &checkpoint);
242 state->offset = checkpoint.offset;
243 free(idx);
244 } else {
245 hashcpy(idx->oid.hash, result_sha1);
246 ALLOC_GROW(state->written,
247 state->nr_written + 1,
248 state->alloc_written);
249 state->written[state->nr_written++] = idx;
251 return 0;
254 int index_bulk_checkin(unsigned char *sha1,
255 int fd, size_t size, enum object_type type,
256 const char *path, unsigned flags)
258 int status = deflate_to_pack(&state, sha1, fd, size, type,
259 path, flags);
260 if (!state.plugged)
261 finish_bulk_checkin(&state);
262 return status;
265 void plug_bulk_checkin(void)
267 state.plugged = 1;
270 void unplug_bulk_checkin(void)
272 state.plugged = 0;
273 if (state.f)
274 finish_bulk_checkin(&state);