]> gitweb.ps.run Git - ps-cgit/blob - cgit.c
Fix cache algorithm loophole
[ps-cgit] / cgit.c
1 /* cgit.c: cgi for the git scm
2  *
3  * Copyright (C) 2006 Lars Hjemli
4  *
5  * Licensed under GNU General Public License v2
6  *   (see COPYING for full license text)
7  */
8
9 #include "cgit.h"
10
11 const char cgit_version[] = CGIT_VERSION;
12
13 const char cgit_doctype[] =
14 "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\"\n"
15 "  \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n";
16
17 const char cgit_error[] =
18 "<div class='error'>%s</div>";
19
20 const char cgit_lib_error[] =
21 "<div class='error'>%s: %s</div>";
22
23 int htmlfd = 0;
24
25 char *cgit_root         = "/usr/src/git";
26 char *cgit_root_title   = "Git repository browser";
27 char *cgit_css          = "/cgit.css";
28 char *cgit_logo         = "/git-logo.png";
29 char *cgit_logo_link    = "http://www.kernel.org/pub/software/scm/git/docs/";
30 char *cgit_virtual_root = NULL;
31
32 char *cgit_cache_root   = "/var/cache/cgit";
33
34 int cgit_cache_root_ttl        =  5;
35 int cgit_cache_repo_ttl        =  5;
36 int cgit_cache_dynamic_ttl     =  5;
37 int cgit_cache_static_ttl      = -1;
38 int cgit_cache_max_create_time =  5;
39
40 char *cgit_repo_name    = NULL;
41 char *cgit_repo_desc    = NULL;
42 char *cgit_repo_owner   = NULL;
43
44 int cgit_query_has_symref = 0;
45 int cgit_query_has_sha1   = 0;
46
47 char *cgit_querystring  = NULL;
48 char *cgit_query_repo   = NULL;
49 char *cgit_query_page   = NULL;
50 char *cgit_query_head   = NULL;
51 char *cgit_query_sha1   = NULL;
52
53 struct cacheitem cacheitem;
54
55 int cgit_parse_query(char *txt, configfn fn)
56 {
57         char *t, *value = NULL, c;
58
59         if (!txt)
60                 return 0;
61
62         t = txt = xstrdup(txt);
63  
64         while((c=*t) != '\0') {
65                 if (c=='=') {
66                         *t = '\0';
67                         value = t+1;
68                 } else if (c=='&') {
69                         *t = '\0';
70                         (*fn)(txt, value);
71                         txt = t+1;
72                         value = NULL;
73                 }
74                 t++;
75         }
76         if (t!=txt)
77                 (*fn)(txt, value);
78         return 0;
79 }
80
81 void cgit_global_config_cb(const char *name, const char *value)
82 {
83         if (!strcmp(name, "root"))
84                 cgit_root = xstrdup(value);
85         else if (!strcmp(name, "root-title"))
86                 cgit_root_title = xstrdup(value);
87         else if (!strcmp(name, "css"))
88                 cgit_css = xstrdup(value);
89         else if (!strcmp(name, "logo"))
90                 cgit_logo = xstrdup(value);
91         else if (!strcmp(name, "logo-link"))
92                 cgit_logo_link = xstrdup(value);
93         else if (!strcmp(name, "virtual-root"))
94                 cgit_virtual_root = xstrdup(value);
95 }
96
97 void cgit_repo_config_cb(const char *name, const char *value)
98 {
99         if (!strcmp(name, "name"))
100                 cgit_repo_name = xstrdup(value);
101         else if (!strcmp(name, "desc"))
102                 cgit_repo_desc = xstrdup(value);
103         else if (!strcmp(name, "owner"))
104                 cgit_repo_owner = xstrdup(value);
105 }
106
107 void cgit_querystring_cb(const char *name, const char *value)
108 {
109         if (!strcmp(name,"r"))
110                 cgit_query_repo = xstrdup(value);
111         else if (!strcmp(name, "p"))
112                 cgit_query_page = xstrdup(value);
113         else if (!strcmp(name, "h")) {
114                 cgit_query_head = xstrdup(value);
115                 cgit_query_has_symref = 1;
116         } else if (!strcmp(name, "id")) {
117                 cgit_query_sha1 = xstrdup(value);
118                 cgit_query_has_sha1 = 1;
119         }
120 }
121
122 char *cgit_repourl(const char *reponame)
123 {
124         if (cgit_virtual_root) {
125                 return fmt("%s/%s/", cgit_virtual_root, reponame);
126         } else {
127                 return fmt("?r=%s", reponame);
128         }
129 }
130
131 char *cgit_pageurl(const char *reponame, const char *pagename, 
132                    const char *query)
133 {
134         if (cgit_virtual_root) {
135                 return fmt("%s/%s/%s/?%s", cgit_virtual_root, reponame, 
136                            pagename, query);
137         } else {
138                 return fmt("?r=%s&p=%s&%s", reponame, pagename, query);
139         }
140 }
141
142 static int cgit_print_branch_cb(const char *refname, const unsigned char *sha1,
143                                 int flags, void *cb_data)
144 {
145         struct commit *commit;
146         char buf[256], *url;
147
148         commit = lookup_commit(sha1);
149         if (commit && !parse_commit(commit)){
150                 html("<tr><td>");
151                 url = cgit_pageurl(cgit_query_repo, "log", 
152                                    fmt("h=%s", refname));
153                 html_link_open(url, NULL, NULL);
154                 strncpy(buf, refname, sizeof(buf));
155                 html_txt(buf);
156                 html_link_close();
157                 html("</td><td>");
158                 pretty_print_commit(CMIT_FMT_ONELINE, commit, ~0, buf,
159                                     sizeof(buf), 0, NULL, NULL, 0);
160                 html_txt(buf);
161                 html("</td></tr>\n");
162         } else {
163                 html("<tr><td>");
164                 html_txt(buf);
165                 html("</td><td>");
166                 htmlf("*** bad ref %s", sha1_to_hex(sha1));
167                 html("</td></tr>\n");
168         }
169         return 0;
170 }
171
172 /* Sun, 06 Nov 1994 08:49:37 GMT */
173 static char *http_date(time_t t)
174 {
175         static char day[][4] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
176         static char month[][4] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
177                                   "Jul", "Aug", "Sep", "Oct", "Now", "Dec"};
178         struct tm *tm = gmtime(&t);
179         return fmt("%s, %02d %s %04d %02d:%02d:%02d GMT", day[tm->tm_wday],
180                    tm->tm_mday, month[tm->tm_mon], 1900+tm->tm_year,
181                    tm->tm_hour, tm->tm_min, tm->tm_sec);
182 }
183
184 static int ttl_seconds(int ttl)
185 {
186         if (ttl<0)
187                 return 60 * 60 * 24 * 365;
188         else 
189                 return ttl * 60;
190 }
191
192 static void cgit_print_docstart(char *title)
193 {
194         html("Content-Type: text/html; charset=utf-8\n");
195         htmlf("Last-Modified: %s\n", http_date(cacheitem.st.st_mtime));
196         htmlf("Expires: %s\n", http_date(cacheitem.st.st_mtime + 
197                                          ttl_seconds(cacheitem.ttl)));
198         html("\n");
199         html(cgit_doctype);
200         html("<html>\n");
201         html("<head>\n");
202         html("<title>");
203         html_txt(title);
204         html("</title>\n");
205         htmlf("<meta name='generator' content='cgit v%s'/>\n", cgit_version);
206         html("<link rel='stylesheet' type='text/css' href='");
207         html_attr(cgit_css);
208         html("'/>\n");
209         html("</head>\n");
210         html("<body>\n");
211 }
212
213 static void cgit_print_docend()
214 {
215         html("</body>\n</html>\n");
216 }
217
218 static void cgit_print_pageheader(char *title)
219 {
220         html("<div id='header'>");
221         htmlf("<a href='%s'>", cgit_logo_link);
222         htmlf("<img id='logo' src='%s'/>\n", cgit_logo);
223         htmlf("</a>");
224         html_txt(title);
225         html("</div>");
226 }
227
228 static void cgit_print_repolist()
229 {
230         DIR *d;
231         struct dirent *de;
232         struct stat st;
233         char *name;
234
235         chdir(cgit_root);
236         cgit_print_docstart(cgit_root_title);
237         cgit_print_pageheader(cgit_root_title);
238
239         if (!(d = opendir("."))) {
240                 htmlf(cgit_lib_error, "Unable to scan repository directory",
241                       strerror(errno));
242                 cgit_print_docend();
243                 return;
244         }
245
246         html("<h2>Repositories</h2>\n");
247         html("<table class='list'>");
248         html("<tr><th>Name</th><th>Description</th><th>Owner</th></tr>\n");
249         while ((de = readdir(d)) != NULL) {
250                 if (de->d_name[0] == '.')
251                         continue;
252                 if (stat(de->d_name, &st) < 0)
253                         continue;
254                 if (!S_ISDIR(st.st_mode))
255                         continue;
256
257                 cgit_repo_name = cgit_repo_desc = cgit_repo_owner = NULL;
258                 name = fmt("%s/info/cgit", de->d_name);
259                 if (cgit_read_config(name, cgit_repo_config_cb))
260                         continue;
261
262                 html("<tr><td>");
263                 html_link_open(cgit_repourl(de->d_name), NULL, NULL);
264                 html_txt(cgit_repo_name);
265                 html_link_close();
266                 html("</td><td>");
267                 html_txt(cgit_repo_desc);
268                 html("</td><td>");
269                 html_txt(cgit_repo_owner);
270                 html("</td></tr>\n");
271         }
272         closedir(d);
273         html("</table>");
274         cgit_print_docend();
275 }
276
277 static void cgit_print_branches()
278 {
279         html("<table class='list'>");
280         html("<tr><th>Branch name</th><th>Head commit</th></tr>\n");
281         for_each_branch_ref(cgit_print_branch_cb, NULL);
282         html("</table>");
283 }
284
285 static int get_one_line(char *txt)
286 {
287         char *t;
288
289         for(t=txt; *t != '\n' && t != '\0'; t++)
290                 ;
291         *t = '\0';
292         return t-txt-1;
293 }
294
295 static void cgit_print_commit_shortlog(struct commit *commit)
296 {
297         char *h, *t, *p; 
298         char *tree = NULL, *author = NULL, *subject = NULL;
299         int len;
300         time_t sec;
301         struct tm *time;
302         char buf[32];
303
304         h = t = commit->buffer;
305         
306         if (strncmp(h, "tree ", 5))
307                 die("Bad commit format: %s", 
308                     sha1_to_hex(commit->object.sha1));
309         
310         len = get_one_line(h);
311         tree = h+5;
312         h += len + 2;
313
314         while (!strncmp(h, "parent ", 7))
315                 h += get_one_line(h) + 2;
316         
317         if (!strncmp(h, "author ", 7)) {
318                 author = h+7;
319                 h += get_one_line(h) + 2;
320                 t = author;
321                 while(t!=h && *t!='<') 
322                         t++;
323                 *t='\0';
324                 p = t;
325                 while(--t!=author && *t==' ')
326                         *t='\0';
327                 while(++p!=h && *p!='>')
328                         ;
329                 while(++p!=h && !isdigit(*p))
330                         ;
331
332                 t = p;
333                 while(++p && isdigit(*p))
334                         ;
335                 *p = '\0';
336                 sec = atoi(t);
337                 time = gmtime(&sec);
338         }
339
340         while((len = get_one_line(h)) > 0)
341                 h += len+2;
342
343         h++;
344         len = get_one_line(h);
345
346         subject = h;
347
348         html("<tr><td>");
349         strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", time);
350         html_txt(buf);
351         html("</td><td>");
352         char *qry = fmt("id=%s", sha1_to_hex(commit->object.sha1));
353         char *url = cgit_pageurl(cgit_query_repo, "view", qry);
354         html_link_open(url, NULL, NULL);
355         html_txt(subject);
356         html_link_close();
357         html("</td><td>");
358         html_txt(author);
359         html("</td></tr>\n");
360 }
361
362 static void cgit_print_log(const char *tip, int ofs, int cnt)
363 {
364         struct rev_info rev;
365         struct commit *commit;
366         const char *argv[2] = {NULL, tip};
367         int n = 0;
368         
369         init_revisions(&rev, NULL);
370         rev.abbrev = DEFAULT_ABBREV;
371         rev.commit_format = CMIT_FMT_DEFAULT;
372         rev.verbose_header = 1;
373         rev.show_root_diff = 0;
374         setup_revisions(2, argv, &rev, NULL);
375         prepare_revision_walk(&rev);
376
377         html("<h2>Log</h2>");
378         html("<table class='list'>");
379         html("<tr><th>Date</th><th>Message</th><th>Author</th></tr>\n");
380         while ((commit = get_revision(&rev)) != NULL && n++ < 100) {
381                 cgit_print_commit_shortlog(commit);
382                 free(commit->buffer);
383                 commit->buffer = NULL;
384                 free_commit_list(commit->parents);
385                 commit->parents = NULL;
386         }
387         html("</table>\n");
388 }
389
390 static void cgit_print_repo_summary()
391 {
392         html("<h2>");
393         html_txt("Repo summary page");
394         html("</h2>");
395         cgit_print_branches();
396 }
397
398 static void cgit_print_object(char *hex)
399 {
400         unsigned char sha1[20];
401         //struct object *object;
402         char type[20];
403         unsigned char *buf;
404         unsigned long size;
405
406         if (get_sha1_hex(hex, sha1)){
407                 htmlf(cgit_error, "Bad hex value");
408                 return;
409         }
410
411         if (sha1_object_info(sha1, type, NULL)){
412                 htmlf(cgit_error, "Bad object name");
413                 return;
414         }
415
416         buf = read_sha1_file(sha1, type, &size);
417         if (!buf) {
418                 htmlf(cgit_error, "Error reading object");
419                 return;
420         }
421
422         buf[size] = '\0';
423         html("<h2>Object view</h2>");
424         htmlf("sha1=%s<br/>type=%s<br/>size=%i<br/>", hex, type, size);
425         html("<pre>");
426         html_txt(buf);
427         html("</pre>");
428 }
429
430 static void cgit_print_repo_page()
431 {
432         if (chdir(fmt("%s/%s", cgit_root, cgit_query_repo)) || 
433             cgit_read_config("info/cgit", cgit_repo_config_cb)) {
434                 char *title = fmt("%s - %s", cgit_root_title, "Bad request");
435                 cgit_print_docstart(title);
436                 cgit_print_pageheader(title);
437                 htmlf(cgit_lib_error, "Unable to scan repository",
438                       strerror(errno));
439                 cgit_print_docend();
440                 return;
441         }
442         setenv("GIT_DIR", fmt("%s/%s", cgit_root, cgit_query_repo), 1);
443         char *title = fmt("%s - %s", cgit_repo_name, cgit_repo_desc);
444         cgit_print_docstart(title);
445         cgit_print_pageheader(title);
446         if (!cgit_query_page)
447                 cgit_print_repo_summary();
448         else if (!strcmp(cgit_query_page, "log")) {
449                 cgit_print_log(cgit_query_head, 0, 100);
450         } else if (!strcmp(cgit_query_page, "view")) {
451                 cgit_print_object(cgit_query_sha1);
452         }
453         cgit_print_docend();
454 }
455
456 static void cgit_fill_cache(struct cacheitem *item)
457 {
458         htmlfd = item->fd;
459         item->st.st_mtime = time(NULL);
460         if (cgit_query_repo)
461                 cgit_print_repo_page();
462         else
463                 cgit_print_repolist();
464 }
465
466 static void cgit_refresh_cache(struct cacheitem *item)
467 {
468         cache_prepare(item);
469  top:
470         if (!cache_exist(item)) {
471                 if (!cache_lock(item)) {
472                         sched_yield();
473                         goto top;
474                 }
475                 if (!cache_exist(item))
476                         cgit_fill_cache(item);
477                 cache_unlock(item);
478         } else if (cache_expired(item) && cache_lock(item)) {
479                 if (cache_expired(item))
480                         cgit_fill_cache(item);
481                 cache_unlock(item);
482         }
483 }
484
485 static void cgit_print_cache(struct cacheitem *item)
486 {
487         static char buf[4096];
488         ssize_t i;
489
490         int fd = open(item->name, O_RDONLY);
491         if (fd<0)
492                 die("Unable to open cached file %s", item->name);
493
494         while((i=read(fd, buf, sizeof(buf))) > 0)
495                 write(STDOUT_FILENO, buf, i);
496
497         close(fd);
498 }
499
500 int main(int argc, const char **argv)
501 {
502         cgit_read_config("/etc/cgitrc", cgit_global_config_cb);
503         cgit_querystring = xstrdup(getenv("QUERY_STRING"));
504         cgit_parse_query(cgit_querystring, cgit_querystring_cb);
505         cgit_refresh_cache(&cacheitem);
506         cgit_print_cache(&cacheitem);
507         return 0;
508 }