Merge branch 'mh/maint-revisions-doc'
[git] / vcs-svn / svndump.c
1 /*
2  * Parse and rearrange a svnadmin dump.
3  * Create the dump with:
4  * svnadmin dump --incremental -r<startrev>:<endrev> <repository> >outfile
5  *
6  * Licensed under a two-clause BSD-style license.
7  * See LICENSE for details.
8  */
9
10 #include "cache.h"
11 #include "repo_tree.h"
12 #include "fast_export.h"
13 #include "line_buffer.h"
14 #include "strbuf.h"
15 #include "svndump.h"
16
17 /*
18  * Compare start of string to literal of equal length;
19  * must be guarded by length test.
20  */
21 #define constcmp(s, ref) memcmp(s, ref, sizeof(ref) - 1)
22
23 #define REPORT_FILENO 3
24
25 #define NODEACT_REPLACE 4
26 #define NODEACT_DELETE 3
27 #define NODEACT_ADD 2
28 #define NODEACT_CHANGE 1
29 #define NODEACT_UNKNOWN 0
30
31 /* States: */
32 #define DUMP_CTX 0      /* dump metadata */
33 #define REV_CTX  1      /* revision metadata */
34 #define NODE_CTX 2      /* node metadata */
35 #define INTERNODE_CTX 3 /* between nodes */
36
37 #define DATE_RFC2822_LEN 31
38
39 static struct line_buffer input = LINE_BUFFER_INIT;
40
41 static struct {
42         uint32_t action, srcRev, type;
43         off_t prop_length, text_length;
44         struct strbuf src, dst;
45         uint32_t text_delta, prop_delta;
46 } node_ctx;
47
48 static struct {
49         uint32_t revision;
50         unsigned long timestamp;
51         struct strbuf log, author;
52 } rev_ctx;
53
54 static struct {
55         uint32_t version;
56         struct strbuf uuid, url;
57 } dump_ctx;
58
59 static void reset_node_ctx(char *fname)
60 {
61         node_ctx.type = 0;
62         node_ctx.action = NODEACT_UNKNOWN;
63         node_ctx.prop_length = -1;
64         node_ctx.text_length = -1;
65         strbuf_reset(&node_ctx.src);
66         node_ctx.srcRev = 0;
67         strbuf_reset(&node_ctx.dst);
68         if (fname)
69                 strbuf_addstr(&node_ctx.dst, fname);
70         node_ctx.text_delta = 0;
71         node_ctx.prop_delta = 0;
72 }
73
74 static void reset_rev_ctx(uint32_t revision)
75 {
76         rev_ctx.revision = revision;
77         rev_ctx.timestamp = 0;
78         strbuf_reset(&rev_ctx.log);
79         strbuf_reset(&rev_ctx.author);
80 }
81
82 static void reset_dump_ctx(const char *url)
83 {
84         strbuf_reset(&dump_ctx.url);
85         if (url)
86                 strbuf_addstr(&dump_ctx.url, url);
87         dump_ctx.version = 1;
88         strbuf_reset(&dump_ctx.uuid);
89 }
90
91 static void handle_property(const struct strbuf *key_buf,
92                                 struct strbuf *val,
93                                 uint32_t *type_set)
94 {
95         const char *key = key_buf->buf;
96         size_t keylen = key_buf->len;
97
98         switch (keylen + 1) {
99         case sizeof("svn:log"):
100                 if (constcmp(key, "svn:log"))
101                         break;
102                 if (!val)
103                         die("invalid dump: unsets svn:log");
104                 strbuf_swap(&rev_ctx.log, val);
105                 break;
106         case sizeof("svn:author"):
107                 if (constcmp(key, "svn:author"))
108                         break;
109                 if (!val)
110                         strbuf_reset(&rev_ctx.author);
111                 else
112                         strbuf_swap(&rev_ctx.author, val);
113                 break;
114         case sizeof("svn:date"):
115                 if (constcmp(key, "svn:date"))
116                         break;
117                 if (!val)
118                         die("invalid dump: unsets svn:date");
119                 if (parse_date_basic(val->buf, &rev_ctx.timestamp, NULL))
120                         warning("invalid timestamp: %s", val->buf);
121                 break;
122         case sizeof("svn:executable"):
123         case sizeof("svn:special"):
124                 if (keylen == strlen("svn:executable") &&
125                     constcmp(key, "svn:executable"))
126                         break;
127                 if (keylen == strlen("svn:special") &&
128                     constcmp(key, "svn:special"))
129                         break;
130                 if (*type_set) {
131                         if (!val)
132                                 return;
133                         die("invalid dump: sets type twice");
134                 }
135                 if (!val) {
136                         node_ctx.type = REPO_MODE_BLB;
137                         return;
138                 }
139                 *type_set = 1;
140                 node_ctx.type = keylen == strlen("svn:executable") ?
141                                 REPO_MODE_EXE :
142                                 REPO_MODE_LNK;
143         }
144 }
145
146 static void die_short_read(void)
147 {
148         if (buffer_ferror(&input))
149                 die_errno("error reading dump file");
150         die("invalid dump: unexpected end of file");
151 }
152
153 static void read_props(void)
154 {
155         static struct strbuf key = STRBUF_INIT;
156         static struct strbuf val = STRBUF_INIT;
157         const char *t;
158         /*
159          * NEEDSWORK: to support simple mode changes like
160          *      K 11
161          *      svn:special
162          *      V 1
163          *      *
164          *      D 14
165          *      svn:executable
166          * we keep track of whether a mode has been set and reset to
167          * plain file only if not.  We should be keeping track of the
168          * symlink and executable bits separately instead.
169          */
170         uint32_t type_set = 0;
171         while ((t = buffer_read_line(&input)) && strcmp(t, "PROPS-END")) {
172                 uint32_t len;
173                 const char type = t[0];
174                 int ch;
175
176                 if (!type || t[1] != ' ')
177                         die("invalid property line: %s", t);
178                 len = atoi(&t[2]);
179                 strbuf_reset(&val);
180                 buffer_read_binary(&input, &val, len);
181                 if (val.len < len)
182                         die_short_read();
183
184                 /* Discard trailing newline. */
185                 ch = buffer_read_char(&input);
186                 if (ch == EOF)
187                         die_short_read();
188                 if (ch != '\n')
189                         die("invalid dump: expected newline after %s", val.buf);
190
191                 switch (type) {
192                 case 'K':
193                         strbuf_swap(&key, &val);
194                         continue;
195                 case 'D':
196                         handle_property(&val, NULL, &type_set);
197                         continue;
198                 case 'V':
199                         handle_property(&key, &val, &type_set);
200                         strbuf_reset(&key);
201                         continue;
202                 default:
203                         die("invalid property line: %s", t);
204                 }
205         }
206 }
207
208 static void handle_node(void)
209 {
210         const uint32_t type = node_ctx.type;
211         const int have_props = node_ctx.prop_length != -1;
212         const int have_text = node_ctx.text_length != -1;
213         /*
214          * Old text for this node:
215          *  NULL        - directory or bug
216          *  empty_blob  - empty
217          *  "<dataref>" - data retrievable from fast-import
218          */
219         static const char *const empty_blob = "::empty::";
220         const char *old_data = NULL;
221         uint32_t old_mode = REPO_MODE_BLB;
222
223         if (node_ctx.action == NODEACT_DELETE) {
224                 if (have_text || have_props || node_ctx.srcRev)
225                         die("invalid dump: deletion node has "
226                                 "copyfrom info, text, or properties");
227                 repo_delete(node_ctx.dst.buf);
228                 return;
229         }
230         if (node_ctx.action == NODEACT_REPLACE) {
231                 repo_delete(node_ctx.dst.buf);
232                 node_ctx.action = NODEACT_ADD;
233         }
234         if (node_ctx.srcRev) {
235                 repo_copy(node_ctx.srcRev, node_ctx.src.buf, node_ctx.dst.buf);
236                 if (node_ctx.action == NODEACT_ADD)
237                         node_ctx.action = NODEACT_CHANGE;
238         }
239         if (have_text && type == REPO_MODE_DIR)
240                 die("invalid dump: directories cannot have text attached");
241
242         /*
243          * Find old content (old_data) and decide on the new mode.
244          */
245         if (node_ctx.action == NODEACT_CHANGE && !*node_ctx.dst.buf) {
246                 if (type != REPO_MODE_DIR)
247                         die("invalid dump: root of tree is not a regular file");
248                 old_data = NULL;
249         } else if (node_ctx.action == NODEACT_CHANGE) {
250                 uint32_t mode;
251                 old_data = repo_read_path(node_ctx.dst.buf, &mode);
252                 if (mode == REPO_MODE_DIR && type != REPO_MODE_DIR)
253                         die("invalid dump: cannot modify a directory into a file");
254                 if (mode != REPO_MODE_DIR && type == REPO_MODE_DIR)
255                         die("invalid dump: cannot modify a file into a directory");
256                 node_ctx.type = mode;
257                 old_mode = mode;
258         } else if (node_ctx.action == NODEACT_ADD) {
259                 if (type == REPO_MODE_DIR)
260                         old_data = NULL;
261                 else if (have_text)
262                         old_data = empty_blob;
263                 else
264                         die("invalid dump: adds node without text");
265         } else {
266                 die("invalid dump: Node-path block lacks Node-action");
267         }
268
269         /*
270          * Adjust mode to reflect properties.
271          */
272         if (have_props) {
273                 if (!node_ctx.prop_delta)
274                         node_ctx.type = type;
275                 if (node_ctx.prop_length)
276                         read_props();
277         }
278
279         /*
280          * Save the result.
281          */
282         if (type == REPO_MODE_DIR)      /* directories are not tracked. */
283                 return;
284         assert(old_data);
285         if (old_data == empty_blob)
286                 /* For the fast_export_* functions, NULL means empty. */
287                 old_data = NULL;
288         if (!have_text) {
289                 fast_export_modify(node_ctx.dst.buf, node_ctx.type, old_data);
290                 return;
291         }
292         if (!node_ctx.text_delta) {
293                 fast_export_modify(node_ctx.dst.buf, node_ctx.type, "inline");
294                 fast_export_data(node_ctx.type, node_ctx.text_length, &input);
295                 return;
296         }
297         fast_export_modify(node_ctx.dst.buf, node_ctx.type, "inline");
298         fast_export_blob_delta(node_ctx.type, old_mode, old_data,
299                                 node_ctx.text_length, &input);
300 }
301
302 static void begin_revision(void)
303 {
304         if (!rev_ctx.revision)  /* revision 0 gets no git commit. */
305                 return;
306         fast_export_begin_commit(rev_ctx.revision, rev_ctx.author.buf,
307                 &rev_ctx.log, dump_ctx.uuid.buf, dump_ctx.url.buf,
308                 rev_ctx.timestamp);
309 }
310
311 static void end_revision(void)
312 {
313         if (rev_ctx.revision)
314                 fast_export_end_commit(rev_ctx.revision);
315 }
316
317 void svndump_read(const char *url)
318 {
319         char *val;
320         char *t;
321         uint32_t active_ctx = DUMP_CTX;
322         uint32_t len;
323
324         reset_dump_ctx(url);
325         while ((t = buffer_read_line(&input))) {
326                 val = strchr(t, ':');
327                 if (!val)
328                         continue;
329                 val++;
330                 if (*val != ' ')
331                         continue;
332                 val++;
333
334                 /* strlen(key) + 1 */
335                 switch (val - t - 1) {
336                 case sizeof("SVN-fs-dump-format-version"):
337                         if (constcmp(t, "SVN-fs-dump-format-version"))
338                                 continue;
339                         dump_ctx.version = atoi(val);
340                         if (dump_ctx.version > 3)
341                                 die("expected svn dump format version <= 3, found %"PRIu32,
342                                     dump_ctx.version);
343                         break;
344                 case sizeof("UUID"):
345                         if (constcmp(t, "UUID"))
346                                 continue;
347                         strbuf_reset(&dump_ctx.uuid);
348                         strbuf_addstr(&dump_ctx.uuid, val);
349                         break;
350                 case sizeof("Revision-number"):
351                         if (constcmp(t, "Revision-number"))
352                                 continue;
353                         if (active_ctx == NODE_CTX)
354                                 handle_node();
355                         if (active_ctx == REV_CTX)
356                                 begin_revision();
357                         if (active_ctx != DUMP_CTX)
358                                 end_revision();
359                         active_ctx = REV_CTX;
360                         reset_rev_ctx(atoi(val));
361                         break;
362                 case sizeof("Node-path"):
363                         if (constcmp(t, "Node-"))
364                                 continue;
365                         if (!constcmp(t + strlen("Node-"), "path")) {
366                                 if (active_ctx == NODE_CTX)
367                                         handle_node();
368                                 if (active_ctx == REV_CTX)
369                                         begin_revision();
370                                 active_ctx = NODE_CTX;
371                                 reset_node_ctx(val);
372                                 break;
373                         }
374                         if (constcmp(t + strlen("Node-"), "kind"))
375                                 continue;
376                         if (!strcmp(val, "dir"))
377                                 node_ctx.type = REPO_MODE_DIR;
378                         else if (!strcmp(val, "file"))
379                                 node_ctx.type = REPO_MODE_BLB;
380                         else
381                                 fprintf(stderr, "Unknown node-kind: %s\n", val);
382                         break;
383                 case sizeof("Node-action"):
384                         if (constcmp(t, "Node-action"))
385                                 continue;
386                         if (!strcmp(val, "delete")) {
387                                 node_ctx.action = NODEACT_DELETE;
388                         } else if (!strcmp(val, "add")) {
389                                 node_ctx.action = NODEACT_ADD;
390                         } else if (!strcmp(val, "change")) {
391                                 node_ctx.action = NODEACT_CHANGE;
392                         } else if (!strcmp(val, "replace")) {
393                                 node_ctx.action = NODEACT_REPLACE;
394                         } else {
395                                 fprintf(stderr, "Unknown node-action: %s\n", val);
396                                 node_ctx.action = NODEACT_UNKNOWN;
397                         }
398                         break;
399                 case sizeof("Node-copyfrom-path"):
400                         if (constcmp(t, "Node-copyfrom-path"))
401                                 continue;
402                         strbuf_reset(&node_ctx.src);
403                         strbuf_addstr(&node_ctx.src, val);
404                         break;
405                 case sizeof("Node-copyfrom-rev"):
406                         if (constcmp(t, "Node-copyfrom-rev"))
407                                 continue;
408                         node_ctx.srcRev = atoi(val);
409                         break;
410                 case sizeof("Text-content-length"):
411                         if (constcmp(t, "Text") && constcmp(t, "Prop"))
412                                 continue;
413                         if (constcmp(t + 4, "-content-length"))
414                                 continue;
415                         {
416                                 char *end;
417                                 uintmax_t len;
418
419                                 len = strtoumax(val, &end, 10);
420                                 if (!isdigit(*val) || *end)
421                                         die("invalid dump: non-numeric length %s", val);
422                                 if (len > maximum_signed_value_of_type(off_t))
423                                         die("unrepresentable length in dump: %s", val);
424
425                                 if (*t == 'T')
426                                         node_ctx.text_length = (off_t) len;
427                                 else
428                                         node_ctx.prop_length = (off_t) len;
429                                 break;
430                         }
431                 case sizeof("Text-delta"):
432                         if (!constcmp(t, "Text-delta")) {
433                                 node_ctx.text_delta = !strcmp(val, "true");
434                                 break;
435                         }
436                         if (constcmp(t, "Prop-delta"))
437                                 continue;
438                         node_ctx.prop_delta = !strcmp(val, "true");
439                         break;
440                 case sizeof("Content-length"):
441                         if (constcmp(t, "Content-length"))
442                                 continue;
443                         len = atoi(val);
444                         t = buffer_read_line(&input);
445                         if (!t)
446                                 die_short_read();
447                         if (*t)
448                                 die("invalid dump: expected blank line after content length header");
449                         if (active_ctx == REV_CTX) {
450                                 read_props();
451                         } else if (active_ctx == NODE_CTX) {
452                                 handle_node();
453                                 active_ctx = INTERNODE_CTX;
454                         } else {
455                                 fprintf(stderr, "Unexpected content length header: %"PRIu32"\n", len);
456                                 if (buffer_skip_bytes(&input, len) != len)
457                                         die_short_read();
458                         }
459                 }
460         }
461         if (buffer_ferror(&input))
462                 die_short_read();
463         if (active_ctx == NODE_CTX)
464                 handle_node();
465         if (active_ctx == REV_CTX)
466                 begin_revision();
467         if (active_ctx != DUMP_CTX)
468                 end_revision();
469 }
470
471 int svndump_init(const char *filename)
472 {
473         if (buffer_init(&input, filename))
474                 return error("cannot open %s: %s", filename, strerror(errno));
475         fast_export_init(REPORT_FILENO);
476         strbuf_init(&dump_ctx.uuid, 4096);
477         strbuf_init(&dump_ctx.url, 4096);
478         strbuf_init(&rev_ctx.log, 4096);
479         strbuf_init(&rev_ctx.author, 4096);
480         strbuf_init(&node_ctx.src, 4096);
481         strbuf_init(&node_ctx.dst, 4096);
482         reset_dump_ctx(NULL);
483         reset_rev_ctx(0);
484         reset_node_ctx(NULL);
485         return 0;
486 }
487
488 void svndump_deinit(void)
489 {
490         fast_export_deinit();
491         reset_dump_ctx(NULL);
492         reset_rev_ctx(0);
493         reset_node_ctx(NULL);
494         strbuf_release(&rev_ctx.log);
495         strbuf_release(&node_ctx.src);
496         strbuf_release(&node_ctx.dst);
497         if (buffer_deinit(&input))
498                 fprintf(stderr, "Input error\n");
499         if (ferror(stdout))
500                 fprintf(stderr, "Output error\n");
501 }
502
503 void svndump_reset(void)
504 {
505         strbuf_release(&dump_ctx.uuid);
506         strbuf_release(&dump_ctx.url);
507         strbuf_release(&rev_ctx.log);
508         strbuf_release(&rev_ctx.author);
509 }