ui-snapshot.c

   1 /* ui-snapshot.c: generate snapshot of a commit
   2  *
   3  * Copyright (C) 2006 Lars Hjemli
   4  * Copyright (C) 2012 Jason A. Donenfeld <Jason@zx2c4.com>
   5  *
   6  * Licensed under GNU General Public License v2
   7  *   (see COPYING for full license text)
   8  */
   9
  10 #include "cgit.h"
  11 #include "html.h"
  12 #include "ui-shared.h"
  13
  14 static int write_compressed_tar_archive(struct archiver_args *args, char *filter_argv[])
  15 {
  16         int rv;
  17         struct cgit_filter f;
  18
  19         f.cmd = filter_argv[0];
  20         f.argv = filter_argv;
  21         cgit_open_filter(&f);
  22         rv = write_tar_archive(args);
  23         cgit_close_filter(&f);
  24         return rv;
  25 }
  26
  27 static int write_tar_gzip_archive(struct archiver_args *args)
  28 {
  29         char *argv[] = { "gzip", "-n", NULL };
  30         return write_compressed_tar_archive(args, argv);
  31 }
  32
  33 static int write_tar_bzip2_archive(struct archiver_args *args)
  34 {
  35         char *argv[] = { "bzip2", NULL };
  36         return write_compressed_tar_archive(args, argv);
  37 }
  38
  39 static int write_tar_xz_archive(struct archiver_args *args)
  40 {
  41         char *argv[] = { "xz", NULL };
  42         return write_compressed_tar_archive(args, argv);
  43 }
  44
  45 const struct cgit_snapshot_format cgit_snapshot_formats[] = {
  46         { ".zip", "application/x-zip", write_zip_archive, 0x01 },
  47         { ".tar.gz", "application/x-gzip", write_tar_gzip_archive, 0x02 },
  48         { ".tar.bz2", "application/x-bzip2", write_tar_bzip2_archive, 0x04 },
  49         { ".tar", "application/x-tar", write_tar_archive, 0x08 },
  50         { ".tar.xz", "application/x-xz", write_tar_xz_archive, 0x10 },
  51         {}
  52 };
  53
  54 static const struct cgit_snapshot_format *get_format(const char *filename)
  55 {
  56         const struct cgit_snapshot_format *fmt;
  57         int fl, sl;
  58
  59         fl = strlen(filename);
  60         for(fmt = cgit_snapshot_formats; fmt->suffix; fmt++) {
  61                 sl = strlen(fmt->suffix);
  62                 if (sl >= fl)
  63                         continue;
  64                 if (!strcmp(fmt->suffix, filename + fl - sl))
  65                         return fmt;
  66         }
  67         return NULL;
  68 }
  69
  70 static int make_snapshot(const struct cgit_snapshot_format *format,
  71                          const char *hex, const char *prefix,
  72                          const char *filename)
  73 {
  74         struct archiver_args args;
  75         struct commit *commit;
  76         unsigned char sha1[20];
  77
  78         if(get_sha1(hex, sha1)) {
  79                 cgit_print_error(fmt("Bad object id: %s", hex));
  80                 return 1;
  81         }
  82         commit = lookup_commit_reference(sha1);
  83         if(!commit) {
  84                 cgit_print_error(fmt("Not a commit reference: %s", hex));
  85                 return 1;
  86         }
  87         memset(&args, 0, sizeof(args));
  88         if (prefix) {
  89                 args.base = fmt("%s/", prefix);
  90                 args.baselen = strlen(prefix) + 1;
  91         } else {
  92                 args.base = "";
  93                 args.baselen = 0;
  94         }
  95         args.tree = commit->tree;
  96         args.time = commit->date;
  97         args.compression_level = Z_DEFAULT_COMPRESSION;
  98         ctx.page.mimetype = xstrdup(format->mimetype);
  99         ctx.page.filename = xstrdup(filename);
 100         cgit_print_http_headers(&ctx);
 101         format->write_func(&args);
 102         return 0;
 103 }
 104
 105 /* Try to guess the requested revision from the requested snapshot name.
 106  * First the format extension is stripped, e.g. "cgit-0.7.2.tar.gz" become
 107  * "cgit-0.7.2". If this is a valid commit object name we've got a winner.
 108  * Otherwise, if the snapshot name has a prefix matching the result from
 109  * repo_basename(), we strip the basename and any following '-' and '_'
 110  * characters ("cgit-0.7.2" -> "0.7.2") and check the resulting name once
 111  * more. If this still isn't a valid commit object name, we check if pre-
 112  * pending a 'v' to the remaining snapshot name ("0.7.2" -> "v0.7.2") gives
 113  * us something valid.
 114  */
 115 static const char *get_ref_from_filename(const char *url, const char *filename,
 116                                          const struct cgit_snapshot_format *format)
 117 {
 118         const char *reponame;
 119         unsigned char sha1[20];
 120         char *snapshot;
 121
 122         snapshot = xstrdup(filename);
 123         snapshot[strlen(snapshot) - strlen(format->suffix)] = '\0';
 124
 125         if (get_sha1(snapshot, sha1) == 0)
 126                 return snapshot;
 127
 128         reponame = cgit_repobasename(url);
 129         if (prefixcmp(snapshot, reponame) == 0) {
 130                 snapshot += strlen(reponame);
 131                 while (snapshot && (*snapshot == '-' || *snapshot == '_'))
 132                         snapshot++;
 133         }
 134
 135         if (get_sha1(snapshot, sha1) == 0)
 136                 return snapshot;
 137
 138         snapshot = fmt("v%s", snapshot);
 139         if (get_sha1(snapshot, sha1) == 0)
 140                 return snapshot;
 141
 142         return NULL;
 143 }
 144
 145 void show_error(char *msg)
 146 {
 147         ctx.page.mimetype = "text/html";
 148         cgit_print_http_headers(&ctx);
 149         cgit_print_docstart(&ctx);
 150         cgit_print_pageheader(&ctx);
 151         cgit_print_error(msg);
 152         cgit_print_docend();
 153 }
 154
 155 void cgit_print_snapshot(const char *head, const char *hex,
 156                          const char *filename, int snapshots, int dwim)
 157 {
 158         const struct cgit_snapshot_format* f;
 159         char *prefix = NULL;
 160
 161         if (!filename) {
 162                 show_error("No snapshot name specified");
 163                 return;
 164         }
 165
 166         f = get_format(filename);
 167         if (!f) {
 168                 show_error(xstrdup(fmt("Unsupported snapshot format: %s",
 169                                        filename)));
 170                 return;
 171         }
 172
 173         if (!hex && dwim) {
 174                 hex = get_ref_from_filename(ctx.repo->url, filename, f);
 175                 if (hex == NULL) {
 176                         html_status(404, "Not found", 0);
 177                         return;
 178                 }
 179                 prefix = xstrdup(filename);
 180                 prefix[strlen(filename) - strlen(f->suffix)] = '\0';
 181         }
 182
 183         if (!hex)
 184                 hex = head;
 185
 186         if (!prefix)
 187                 prefix = xstrdup(cgit_repobasename(ctx.repo->url));
 188
 189         make_snapshot(f, hex, prefix, filename);
 190         free(prefix);
 191 }