strbuf_read(): skip unnecessary strbuf_grow() at eof
[git] / remote-testsvn.c
1 #include "cache.h"
2 #include "remote.h"
3 #include "strbuf.h"
4 #include "url.h"
5 #include "exec_cmd.h"
6 #include "run-command.h"
7 #include "vcs-svn/svndump.h"
8 #include "notes.h"
9 #include "argv-array.h"
10
11 static const char *url;
12 static int dump_from_file;
13 static const char *private_ref;
14 static const char *remote_ref = "refs/heads/master";
15 static const char *marksfilename, *notes_ref;
16 struct rev_note { unsigned int rev_nr; };
17
18 static int cmd_capabilities(const char *line);
19 static int cmd_import(const char *line);
20 static int cmd_list(const char *line);
21
22 typedef int (*input_command_handler)(const char *);
23 struct input_command_entry {
24         const char *name;
25         input_command_handler fn;
26         unsigned char batchable;        /* whether the command starts or is part of a batch */
27 };
28
29 static const struct input_command_entry input_command_list[] = {
30         { "capabilities", cmd_capabilities, 0 },
31         { "import", cmd_import, 1 },
32         { "list", cmd_list, 0 },
33         { NULL, NULL }
34 };
35
36 static int cmd_capabilities(const char *line)
37 {
38         printf("import\n");
39         printf("bidi-import\n");
40         printf("refspec %s:%s\n\n", remote_ref, private_ref);
41         fflush(stdout);
42         return 0;
43 }
44
45 static void terminate_batch(void)
46 {
47         /* terminate a current batch's fast-import stream */
48         printf("done\n");
49         fflush(stdout);
50 }
51
52 /* NOTE: 'ref' refers to a git reference, while 'rev' refers to a svn revision. */
53 static char *read_ref_note(const unsigned char sha1[20])
54 {
55         const unsigned char *note_sha1;
56         char *msg = NULL;
57         unsigned long msglen;
58         enum object_type type;
59
60         init_notes(NULL, notes_ref, NULL, 0);
61         if (!(note_sha1 = get_note(NULL, sha1)))
62                 return NULL;    /* note tree not found */
63         if (!(msg = read_sha1_file(note_sha1, &type, &msglen)))
64                 error("Empty notes tree. %s", notes_ref);
65         else if (!msglen || type != OBJ_BLOB) {
66                 error("Note contains unusable content. "
67                         "Is something else using this notes tree? %s", notes_ref);
68                 free(msg);
69                 msg = NULL;
70         }
71         free_notes(NULL);
72         return msg;
73 }
74
75 static int parse_rev_note(const char *msg, struct rev_note *res)
76 {
77         const char *key, *value, *end;
78         size_t len;
79
80         while (*msg) {
81                 end = strchrnul(msg, '\n');
82                 len = end - msg;
83
84                 key = "Revision-number: ";
85                 if (starts_with(msg, key)) {
86                         long i;
87                         char *end;
88                         value = msg + strlen(key);
89                         i = strtol(value, &end, 0);
90                         if (end == value || i < 0 || i > UINT32_MAX)
91                                 return -1;
92                         res->rev_nr = i;
93                         return 0;
94                 }
95                 msg += len + 1;
96         }
97         /* didn't find it */
98         return -1;
99 }
100
101 static int note2mark_cb(const unsigned char *object_sha1,
102                 const unsigned char *note_sha1, char *note_path,
103                 void *cb_data)
104 {
105         FILE *file = (FILE *)cb_data;
106         char *msg;
107         unsigned long msglen;
108         enum object_type type;
109         struct rev_note note;
110
111         if (!(msg = read_sha1_file(note_sha1, &type, &msglen)) ||
112                         !msglen || type != OBJ_BLOB) {
113                 free(msg);
114                 return 1;
115         }
116         if (parse_rev_note(msg, &note))
117                 return 2;
118         if (fprintf(file, ":%d %s\n", note.rev_nr, sha1_to_hex(object_sha1)) < 1)
119                 return 3;
120         return 0;
121 }
122
123 static void regenerate_marks(void)
124 {
125         int ret;
126         FILE *marksfile = fopen(marksfilename, "w+");
127
128         if (!marksfile)
129                 die_errno("Couldn't create mark file %s.", marksfilename);
130         ret = for_each_note(NULL, 0, note2mark_cb, marksfile);
131         if (ret)
132                 die("Regeneration of marks failed, returned %d.", ret);
133         fclose(marksfile);
134 }
135
136 static void check_or_regenerate_marks(int latestrev)
137 {
138         FILE *marksfile;
139         struct strbuf sb = STRBUF_INIT;
140         struct strbuf line = STRBUF_INIT;
141         int found = 0;
142
143         if (latestrev < 1)
144                 return;
145
146         init_notes(NULL, notes_ref, NULL, 0);
147         marksfile = fopen(marksfilename, "r");
148         if (!marksfile) {
149                 regenerate_marks();
150                 marksfile = fopen(marksfilename, "r");
151                 if (!marksfile)
152                         die_errno("cannot read marks file %s!", marksfilename);
153                 fclose(marksfile);
154         } else {
155                 strbuf_addf(&sb, ":%d ", latestrev);
156                 while (strbuf_getline(&line, marksfile, '\n') != EOF) {
157                         if (starts_with(line.buf, sb.buf)) {
158                                 found++;
159                                 break;
160                         }
161                 }
162                 fclose(marksfile);
163                 if (!found)
164                         regenerate_marks();
165         }
166         free_notes(NULL);
167         strbuf_release(&sb);
168         strbuf_release(&line);
169 }
170
171 static int cmd_import(const char *line)
172 {
173         int code;
174         int dumpin_fd;
175         char *note_msg;
176         unsigned char head_sha1[20];
177         unsigned int startrev;
178         struct argv_array svndump_argv = ARGV_ARRAY_INIT;
179         struct child_process svndump_proc;
180
181         if (read_ref(private_ref, head_sha1))
182                 startrev = 0;
183         else {
184                 note_msg = read_ref_note(head_sha1);
185                 if(note_msg == NULL) {
186                         warning("No note found for %s.", private_ref);
187                         startrev = 0;
188                 } else {
189                         struct rev_note note = { 0 };
190                         if (parse_rev_note(note_msg, &note))
191                                 die("Revision number couldn't be parsed from note.");
192                         startrev = note.rev_nr + 1;
193                         free(note_msg);
194                 }
195         }
196         check_or_regenerate_marks(startrev - 1);
197
198         if (dump_from_file) {
199                 dumpin_fd = open(url, O_RDONLY);
200                 if(dumpin_fd < 0)
201                         die_errno("Couldn't open svn dump file %s.", url);
202         } else {
203                 memset(&svndump_proc, 0, sizeof(struct child_process));
204                 svndump_proc.out = -1;
205                 argv_array_push(&svndump_argv, "svnrdump");
206                 argv_array_push(&svndump_argv, "dump");
207                 argv_array_push(&svndump_argv, url);
208                 argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
209                 svndump_proc.argv = svndump_argv.argv;
210
211                 code = start_command(&svndump_proc);
212                 if (code)
213                         die("Unable to start %s, code %d", svndump_proc.argv[0], code);
214                 dumpin_fd = svndump_proc.out;
215         }
216         /* setup marks file import/export */
217         printf("feature import-marks-if-exists=%s\n"
218                         "feature export-marks=%s\n", marksfilename, marksfilename);
219
220         svndump_init_fd(dumpin_fd, STDIN_FILENO);
221         svndump_read(url, private_ref, notes_ref);
222         svndump_deinit();
223         svndump_reset();
224
225         close(dumpin_fd);
226         if (!dump_from_file) {
227                 code = finish_command(&svndump_proc);
228                 if (code)
229                         warning("%s, returned %d", svndump_proc.argv[0], code);
230                 argv_array_clear(&svndump_argv);
231         }
232
233         return 0;
234 }
235
236 static int cmd_list(const char *line)
237 {
238         printf("? %s\n\n", remote_ref);
239         fflush(stdout);
240         return 0;
241 }
242
243 static int do_command(struct strbuf *line)
244 {
245         const struct input_command_entry *p = input_command_list;
246         static struct string_list batchlines = STRING_LIST_INIT_DUP;
247         static const struct input_command_entry *batch_cmd;
248         /*
249          * commands can be grouped together in a batch.
250          * Batches are ended by \n. If no batch is active the program ends.
251          * During a batch all lines are buffered and passed to the handler function
252          * when the batch is terminated.
253          */
254         if (line->len == 0) {
255                 if (batch_cmd) {
256                         struct string_list_item *item;
257                         for_each_string_list_item(item, &batchlines)
258                                 batch_cmd->fn(item->string);
259                         terminate_batch();
260                         batch_cmd = NULL;
261                         string_list_clear(&batchlines, 0);
262                         return 0;       /* end of the batch, continue reading other commands. */
263                 }
264                 return 1;       /* end of command stream, quit */
265         }
266         if (batch_cmd) {
267                 if (!starts_with(batch_cmd->name, line->buf))
268                         die("Active %s batch interrupted by %s", batch_cmd->name, line->buf);
269                 /* buffer batch lines */
270                 string_list_append(&batchlines, line->buf);
271                 return 0;
272         }
273
274         for (p = input_command_list; p->name; p++) {
275                 if (starts_with(line->buf, p->name) && (strlen(p->name) == line->len ||
276                                 line->buf[strlen(p->name)] == ' ')) {
277                         if (p->batchable) {
278                                 batch_cmd = p;
279                                 string_list_append(&batchlines, line->buf);
280                                 return 0;
281                         }
282                         return p->fn(line->buf);
283                 }
284         }
285         die("Unknown command '%s'\n", line->buf);
286         return 0;
287 }
288
289 int main(int argc, char **argv)
290 {
291         struct strbuf buf = STRBUF_INIT, url_sb = STRBUF_INIT,
292                         private_ref_sb = STRBUF_INIT, marksfilename_sb = STRBUF_INIT,
293                         notes_ref_sb = STRBUF_INIT;
294         static struct remote *remote;
295         const char *url_in;
296
297         git_extract_argv0_path(argv[0]);
298         setup_git_directory();
299         if (argc < 2 || argc > 3) {
300                 usage("git-remote-svn <remote-name> [<url>]");
301                 return 1;
302         }
303
304         remote = remote_get(argv[1]);
305         url_in = (argc == 3) ? argv[2] : remote->url[0];
306
307         if (starts_with(url_in, "file://")) {
308                 dump_from_file = 1;
309                 url = url_decode(url_in + sizeof("file://")-1);
310         } else {
311                 dump_from_file = 0;
312                 end_url_with_slash(&url_sb, url_in);
313                 url = url_sb.buf;
314         }
315
316         strbuf_addf(&private_ref_sb, "refs/svn/%s/master", remote->name);
317         private_ref = private_ref_sb.buf;
318
319         strbuf_addf(&notes_ref_sb, "refs/notes/%s/revs", remote->name);
320         notes_ref = notes_ref_sb.buf;
321
322         strbuf_addf(&marksfilename_sb, "%s/info/fast-import/remote-svn/%s.marks",
323                 get_git_dir(), remote->name);
324         marksfilename = marksfilename_sb.buf;
325
326         while (1) {
327                 if (strbuf_getline(&buf, stdin, '\n') == EOF) {
328                         if (ferror(stdin))
329                                 die("Error reading command stream");
330                         else
331                                 die("Unexpected end of command stream");
332                 }
333                 if (do_command(&buf))
334                         break;
335                 strbuf_reset(&buf);
336         }
337
338         strbuf_release(&buf);
339         strbuf_release(&url_sb);
340         strbuf_release(&private_ref_sb);
341         strbuf_release(&notes_ref_sb);
342         strbuf_release(&marksfilename_sb);
343         return 0;
344 }