archive.c

   1 #include "cache.h"
   2 #include "commit.h"
   3 #include "tree-walk.h"
   4 #include "attr.h"
   5 #include "archive.h"
   6
   7 static const char archive_usage[] = \
   8 "git archive --format=<fmt> [--prefix=<prefix>/] [--verbose] [<extra>] <tree-ish> [path...]";
   9
  10 #define USES_ZLIB_COMPRESSION 1
  11
  12 const struct archiver archivers[] = {
  13         { "tar", write_tar_archive },
  14         { "zip", write_zip_archive, USES_ZLIB_COMPRESSION },
  15 };
  16
  17 static void format_subst(const struct commit *commit,
  18                          const char *src, size_t len,
  19                          struct strbuf *buf)
  20 {
  21         char *to_free = NULL;
  22         struct strbuf fmt;
  23
  24         if (src == buf->buf)
  25                 to_free = strbuf_detach(buf, NULL);
  26         strbuf_init(&fmt, 0);
  27         for (;;) {
  28                 const char *b, *c;
  29
  30                 b = memmem(src, len, "$Format:", 8);
  31                 if (!b)
  32                         break;
  33                 c = memchr(b + 8, '$', (src + len) - b - 8);
  34                 if (!c)
  35                         break;
  36
  37                 strbuf_reset(&fmt);
  38                 strbuf_add(&fmt, b + 8, c - b - 8);
  39
  40                 strbuf_add(buf, src, b - src);
  41                 format_commit_message(commit, fmt.buf, buf);
  42                 len -= c + 1 - src;
  43                 src  = c + 1;
  44         }
  45         strbuf_add(buf, src, len);
  46         strbuf_release(&fmt);
  47         free(to_free);
  48 }
  49
  50 static void *sha1_file_to_archive(const char *path, const unsigned char *sha1,
  51                 unsigned int mode, enum object_type *type,
  52                 unsigned long *sizep, const struct commit *commit)
  53 {
  54         void *buffer;
  55
  56         buffer = read_sha1_file(sha1, type, sizep);
  57         if (buffer && S_ISREG(mode)) {
  58                 struct strbuf buf;
  59                 size_t size = 0;
  60
  61                 strbuf_init(&buf, 0);
  62                 strbuf_attach(&buf, buffer, *sizep, *sizep + 1);
  63                 convert_to_working_tree(path, buf.buf, buf.len, &buf);
  64                 if (commit)
  65                         format_subst(commit, buf.buf, buf.len, &buf);
  66                 buffer = strbuf_detach(&buf, &size);
  67                 *sizep = size;
  68         }
  69
  70         return buffer;
  71 }
  72
  73 static void setup_archive_check(struct git_attr_check *check)
  74 {
  75         static struct git_attr *attr_export_ignore;
  76         static struct git_attr *attr_export_subst;
  77
  78         if (!attr_export_ignore) {
  79                 attr_export_ignore = git_attr("export-ignore", 13);
  80                 attr_export_subst = git_attr("export-subst", 12);
  81         }
  82         check[0].attr = attr_export_ignore;
  83         check[1].attr = attr_export_subst;
  84 }
  85
  86 struct archiver_context {
  87         struct archiver_args *args;
  88         write_archive_entry_fn_t write_entry;
  89 };
  90
  91 static int write_archive_entry(const unsigned char *sha1, const char *base,
  92                 int baselen, const char *filename, unsigned mode, int stage,
  93                 void *context)
  94 {
  95         static struct strbuf path = STRBUF_INIT;
  96         struct archiver_context *c = context;
  97         struct archiver_args *args = c->args;
  98         write_archive_entry_fn_t write_entry = c->write_entry;
  99         struct git_attr_check check[2];
 100         const char *path_without_prefix;
 101         int convert = 0;
 102         int err;
 103         enum object_type type;
 104         unsigned long size;
 105         void *buffer;
 106
 107         strbuf_reset(&path);
 108         strbuf_grow(&path, PATH_MAX);
 109         strbuf_add(&path, base, baselen);
 110         strbuf_addstr(&path, filename);
 111         path_without_prefix = path.buf + args->baselen;
 112
 113         setup_archive_check(check);
 114         if (!git_checkattr(path_without_prefix, ARRAY_SIZE(check), check)) {
 115                 if (ATTR_TRUE(check[0].value))
 116                         return 0;
 117                 convert = ATTR_TRUE(check[1].value);
 118         }
 119
 120         if (S_ISDIR(mode) || S_ISGITLINK(mode)) {
 121                 strbuf_addch(&path, '/');
 122                 if (args->verbose)
 123                         fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 124                 err = write_entry(args, sha1, path.buf, path.len, mode, NULL, 0);
 125                 if (err)
 126                         return err;
 127                 return READ_TREE_RECURSIVE;
 128         }
 129
 130         buffer = sha1_file_to_archive(path_without_prefix, sha1, mode,
 131                         &type, &size, convert ? args->commit : NULL);
 132         if (!buffer)
 133                 return error("cannot read %s", sha1_to_hex(sha1));
 134         if (args->verbose)
 135                 fprintf(stderr, "%.*s\n", (int)path.len, path.buf);
 136         err = write_entry(args, sha1, path.buf, path.len, mode, buffer, size);
 137         free(buffer);
 138         return err;
 139 }
 140
 141 int write_archive_entries(struct archiver_args *args,
 142                 write_archive_entry_fn_t write_entry)
 143 {
 144         struct archiver_context context;
 145         int err;
 146
 147         if (args->baselen > 0 && args->base[args->baselen - 1] == '/') {
 148                 size_t len = args->baselen;
 149
 150                 while (len > 1 && args->base[len - 2] == '/')
 151                         len--;
 152                 if (args->verbose)
 153                         fprintf(stderr, "%.*s\n", (int)len, args->base);
 154                 err = write_entry(args, args->tree->object.sha1, args->base,
 155                                 len, 040777, NULL, 0);
 156                 if (err)
 157                         return err;
 158         }
 159
 160         context.args = args;
 161         context.write_entry = write_entry;
 162
 163         err =  read_tree_recursive(args->tree, args->base, args->baselen, 0,
 164                         args->pathspec, write_archive_entry, &context);
 165         if (err == READ_TREE_RECURSIVE)
 166                 err = 0;
 167         return err;
 168 }
 169
 170 static const struct archiver *lookup_archiver(const char *name)
 171 {
 172         int i;
 173
 174         for (i = 0; i < ARRAY_SIZE(archivers); i++) {
 175                 if (!strcmp(name, archivers[i].name))
 176                         return &archivers[i];
 177         }
 178         return NULL;
 179 }
 180
 181 static void parse_pathspec_arg(const char **pathspec,
 182                 struct archiver_args *ar_args)
 183 {
 184         ar_args->pathspec = get_pathspec(ar_args->base, pathspec);
 185 }
 186
 187 static void parse_treeish_arg(const char **argv,
 188                 struct archiver_args *ar_args, const char *prefix)
 189 {
 190         const char *name = argv[0];
 191         const unsigned char *commit_sha1;
 192         time_t archive_time;
 193         struct tree *tree;
 194         const struct commit *commit;
 195         unsigned char sha1[20];
 196
 197         if (get_sha1(name, sha1))
 198                 die("Not a valid object name");
 199
 200         commit = lookup_commit_reference_gently(sha1, 1);
 201         if (commit) {
 202                 commit_sha1 = commit->object.sha1;
 203                 archive_time = commit->date;
 204         } else {
 205                 commit_sha1 = NULL;
 206                 archive_time = time(NULL);
 207         }
 208
 209         tree = parse_tree_indirect(sha1);
 210         if (tree == NULL)
 211                 die("not a tree object");
 212
 213         if (prefix) {
 214                 unsigned char tree_sha1[20];
 215                 unsigned int mode;
 216                 int err;
 217
 218                 err = get_tree_entry(tree->object.sha1, prefix,
 219                                      tree_sha1, &mode);
 220                 if (err || !S_ISDIR(mode))
 221                         die("current working directory is untracked");
 222
 223                 tree = parse_tree_indirect(tree_sha1);
 224         }
 225         ar_args->tree = tree;
 226         ar_args->commit_sha1 = commit_sha1;
 227         ar_args->commit = commit;
 228         ar_args->time = archive_time;
 229 }
 230
 231 static int parse_archive_args(int argc, const char **argv,
 232                 const struct archiver **ar, struct archiver_args *args)
 233 {
 234         const char *format = "tar";
 235         const char *base = "";
 236         int compression_level = -1;
 237         int verbose = 0;
 238         int i;
 239
 240         for (i = 1; i < argc; i++) {
 241                 const char *arg = argv[i];
 242
 243                 if (!strcmp(arg, "--list") || !strcmp(arg, "-l")) {
 244                         for (i = 0; i < ARRAY_SIZE(archivers); i++)
 245                                 printf("%s\n", archivers[i].name);
 246                         exit(0);
 247                 }
 248                 if (!strcmp(arg, "--verbose") || !strcmp(arg, "-v")) {
 249                         verbose = 1;
 250                         continue;
 251                 }
 252                 if (!prefixcmp(arg, "--format=")) {
 253                         format = arg + 9;
 254                         continue;
 255                 }
 256                 if (!prefixcmp(arg, "--prefix=")) {
 257                         base = arg + 9;
 258                         continue;
 259                 }
 260                 if (!strcmp(arg, "--")) {
 261                         i++;
 262                         break;
 263                 }
 264                 if (arg[0] == '-' && isdigit(arg[1]) && arg[2] == '\0') {
 265                         compression_level = arg[1] - '0';
 266                         continue;
 267                 }
 268                 if (arg[0] == '-')
 269                         die("Unknown argument: %s", arg);
 270                 break;
 271         }
 272
 273         /* We need at least one parameter -- tree-ish */
 274         if (argc - 1 < i)
 275                 usage(archive_usage);
 276         *ar = lookup_archiver(format);
 277         if (!*ar)
 278                 die("Unknown archive format '%s'", format);
 279
 280         args->compression_level = Z_DEFAULT_COMPRESSION;
 281         if (compression_level != -1) {
 282                 if ((*ar)->flags & USES_ZLIB_COMPRESSION)
 283                         args->compression_level = compression_level;
 284                 else {
 285                         die("Argument not supported for format '%s': -%d",
 286                                         format, compression_level);
 287                 }
 288         }
 289         args->verbose = verbose;
 290         args->base = base;
 291         args->baselen = strlen(base);
 292
 293         return i;
 294 }
 295
 296 int write_archive(int argc, const char **argv, const char *prefix,
 297                 int setup_prefix)
 298 {
 299         const struct archiver *ar = NULL;
 300         struct archiver_args args;
 301         int tree_idx;
 302
 303         tree_idx = parse_archive_args(argc, argv, &ar, &args);
 304         if (setup_prefix && prefix == NULL)
 305                 prefix = setup_git_directory();
 306
 307         argv += tree_idx;
 308         parse_treeish_arg(argv, &args, prefix);
 309         parse_pathspec_arg(argv + 1, &args);
 310
 311         return ar->write_archive(&args);
 312 }