Andrew's git - gitweb.git/blob

   1#define _XOPEN_SOURCE /* glibc2 needs this */
   2#define __EXTENSIONS__ /* solaris needs this */
   3#include <time.h>
   4#include <ctype.h>
   5#include "cache.h"
   6
   7struct entry {
   8        unsigned char old_sha1[20];
   9        unsigned char new_sha1[20];
  10        int converted;
  11};
  12
  13#define MAXOBJECTS (1000000)
  14
  15static struct entry *convert[MAXOBJECTS];
  16static int nr_convert;
  17
  18static struct entry * convert_entry(unsigned char *sha1);
  19
  20static struct entry *insert_new(unsigned char *sha1, int pos)
  21{
  22        struct entry *new = xmalloc(sizeof(struct entry));
  23        memset(new, 0, sizeof(*new));
  24        memcpy(new->old_sha1, sha1, 20);
  25        memmove(convert + pos + 1, convert + pos, (nr_convert - pos) * sizeof(struct entry *));
  26        convert[pos] = new;
  27        nr_convert++;
  28        if (nr_convert == MAXOBJECTS)
  29                die("you're kidding me - hit maximum object limit");
  30        return new;
  31}
  32
  33static struct entry *lookup_entry(unsigned char *sha1)
  34{
  35        int low = 0, high = nr_convert;
  36
  37        while (low < high) {
  38                int next = (low + high) / 2;
  39                struct entry *n = convert[next];
  40                int cmp = memcmp(sha1, n->old_sha1, 20);
  41                if (!cmp)
  42                        return n;
  43                if (cmp < 0) {
  44                        high = next;
  45                        continue;
  46                }
  47                low = next+1;
  48        }
  49        return insert_new(sha1, low);
  50}
  51
  52static void convert_binary_sha1(void *buffer)
  53{
  54        struct entry *entry = convert_entry(buffer);
  55        memcpy(buffer, entry->new_sha1, 20);
  56}
  57
  58static void convert_ascii_sha1(void *buffer)
  59{
  60        unsigned char sha1[20];
  61        struct entry *entry;
  62
  63        if (get_sha1_hex(buffer, sha1))
  64                die("expected sha1, got '%s'", (char*) buffer);
  65        entry = convert_entry(sha1);
  66        memcpy(buffer, sha1_to_hex(entry->new_sha1), 40);
  67}
  68
  69static unsigned int convert_mode(unsigned int mode)
  70{
  71        unsigned int newmode;
  72
  73        newmode = mode & S_IFMT;
  74        if (S_ISREG(mode))
  75                newmode |= (mode & 0100) ? 0755 : 0644;
  76        return newmode;
  77}
  78
  79static int write_subdirectory(void *buffer, unsigned long size, const char *base, int baselen, unsigned char *result_sha1)
  80{
  81        char *new = xmalloc(size);
  82        unsigned long newlen = 0;
  83        unsigned long used;
  84
  85        used = 0;
  86        while (size) {
  87                int len = 21 + strlen(buffer);
  88                char *path = strchr(buffer, ' ');
  89                unsigned char *sha1;
  90                unsigned int mode;
  91                char *slash, *origpath;
  92
  93                if (!path || sscanf(buffer, "%o", &mode) != 1)
  94                        die("bad tree conversion");
  95                mode = convert_mode(mode);
  96                path++;
  97                if (memcmp(path, base, baselen))
  98                        break;
  99                origpath = path;
 100                path += baselen;
 101                slash = strchr(path, '/');
 102                if (!slash) {
 103                        newlen += sprintf(new + newlen, "%o %s", mode, path);
 104                        new[newlen++] = '\0';
 105                        memcpy(new + newlen, buffer + len - 20, 20);
 106                        newlen += 20;
 107
 108                        used += len;
 109                        size -= len;
 110                        buffer += len;
 111                        continue;
 112                }
 113
 114                newlen += sprintf(new + newlen, "%o %.*s", S_IFDIR, (int)(slash - path), path);
 115                new[newlen++] = 0;
 116                sha1 = (unsigned char *)(new + newlen);
 117                newlen += 20;
 118
 119                len = write_subdirectory(buffer, size, origpath, slash-origpath+1, sha1);
 120
 121                used += len;
 122                size -= len;
 123                buffer += len;
 124        }
 125
 126        write_sha1_file(new, newlen, "tree", result_sha1);
 127        free(new);
 128        return used;
 129}
 130
 131static void convert_tree(void *buffer, unsigned long size, unsigned char *result_sha1)
 132{
 133        void *orig_buffer = buffer;
 134        unsigned long orig_size = size;
 135
 136        while (size) {
 137                int len = 1+strlen(buffer);
 138
 139                convert_binary_sha1(buffer + len);
 140
 141                len += 20;
 142                if (len > size)
 143                        die("corrupt tree object");
 144                size -= len;
 145                buffer += len;
 146        }
 147
 148        write_subdirectory(orig_buffer, orig_size, "", 0, result_sha1);
 149}
 150
 151static unsigned long parse_oldstyle_date(const char *buf)
 152{
 153        char c, *p;
 154        char buffer[100];
 155        struct tm tm;
 156        const char *formats[] = {
 157                "%c",
 158                "%a %b %d %T",
 159                "%Z",
 160                "%Y",
 161                " %Y",
 162                NULL
 163        };
 164        /* We only ever did two timezones in the bad old format .. */
 165        const char *timezones[] = {
 166                "PDT", "PST", "CEST", NULL
 167        };
 168        const char **fmt = formats;
 169
 170        p = buffer;
 171        while (isspace(c = *buf))
 172                buf++;
 173        while ((c = *buf++) != '\n')
 174                *p++ = c;
 175        *p++ = 0;
 176        buf = buffer;
 177        memset(&tm, 0, sizeof(tm));
 178        do {
 179                const char *next = strptime(buf, *fmt, &tm);
 180                if (next) {
 181                        if (!*next)
 182                                return mktime(&tm);
 183                        buf = next;
 184                } else {
 185                        const char **p = timezones;
 186                        while (isspace(*buf))
 187                                buf++;
 188                        while (*p) {
 189                                if (!memcmp(buf, *p, strlen(*p))) {
 190                                        buf += strlen(*p);
 191                                        break;
 192                                }
 193                                p++;
 194                        }
 195                }
 196                fmt++;
 197        } while (*buf && *fmt);
 198        printf("left: %s\n", buf);
 199        return mktime(&tm);                             
 200}
 201
 202static int convert_date_line(char *dst, void **buf, unsigned long *sp)
 203{
 204        unsigned long size = *sp;
 205        char *line = *buf;
 206        char *next = strchr(line, '\n');
 207        char *date = strchr(line, '>');
 208        int len;
 209
 210        if (!next || !date)
 211                die("missing or bad author/committer line %s", line);
 212        next++; date += 2;
 213
 214        *buf = next;
 215        *sp = size - (next - line);
 216
 217        len = date - line;
 218        memcpy(dst, line, len);
 219        dst += len;
 220
 221        /* Is it already in new format? */
 222        if (isdigit(*date)) {
 223                int datelen = next - date;
 224                memcpy(dst, date, datelen);
 225                return len + datelen;
 226        }
 227
 228        /*
 229         * Hacky hacky: one of the sparse old-style commits does not have
 230         * any date at all, but we can fake it by using the committer date.
 231         */
 232        if (*date == '\n' && strchr(next, '>'))
 233                date = strchr(next, '>')+2;
 234
 235        return len + sprintf(dst, "%lu -0700\n", parse_oldstyle_date(date));
 236}
 237
 238static void convert_date(void *buffer, unsigned long size, unsigned char *result_sha1)
 239{
 240        char *new = xmalloc(size + 100);
 241        unsigned long newlen = 0;
 242        
 243        // "tree <sha1>\n"
 244        memcpy(new + newlen, buffer, 46);
 245        newlen += 46;
 246        buffer += 46;
 247        size -= 46;
 248
 249        // "parent <sha1>\n"
 250        while (!memcmp(buffer, "parent ", 7)) {
 251                memcpy(new + newlen, buffer, 48);
 252                newlen += 48;
 253                buffer += 48;
 254                size -= 48;
 255        }
 256
 257        // "author xyz <xyz> date"
 258        newlen += convert_date_line(new + newlen, &buffer, &size);
 259        // "committer xyz <xyz> date"
 260        newlen += convert_date_line(new + newlen, &buffer, &size);
 261
 262        // Rest
 263        memcpy(new + newlen, buffer, size);
 264        newlen += size;
 265
 266        write_sha1_file(new, newlen, "commit", result_sha1);
 267        free(new);      
 268}
 269
 270static void convert_commit(void *buffer, unsigned long size, unsigned char *result_sha1)
 271{
 272        void *orig_buffer = buffer;
 273        unsigned long orig_size = size;
 274
 275        if (memcmp(buffer, "tree ", 5))
 276                die("Bad commit '%s'", (char*) buffer);
 277        convert_ascii_sha1(buffer+5);
 278        buffer += 46;    /* "tree " + "hex sha1" + "\n" */
 279        while (!memcmp(buffer, "parent ", 7)) {
 280                convert_ascii_sha1(buffer+7);
 281                buffer += 48;
 282        }
 283        convert_date(orig_buffer, orig_size, result_sha1);
 284}
 285
 286static struct entry * convert_entry(unsigned char *sha1)
 287{
 288        struct entry *entry = lookup_entry(sha1);
 289        char type[20];
 290        void *buffer, *data;
 291        unsigned long size;
 292
 293        if (entry->converted)
 294                return entry;
 295        data = read_sha1_file(sha1, type, &size);
 296        if (!data)
 297                die("unable to read object %s", sha1_to_hex(sha1));
 298
 299        buffer = xmalloc(size);
 300        memcpy(buffer, data, size);
 301        
 302        if (!strcmp(type, "blob")) {
 303                write_sha1_file(buffer, size, "blob", entry->new_sha1);
 304        } else if (!strcmp(type, "tree"))
 305                convert_tree(buffer, size, entry->new_sha1);
 306        else if (!strcmp(type, "commit"))
 307                convert_commit(buffer, size, entry->new_sha1);
 308        else
 309                die("unknown object type '%s' in %s", type, sha1_to_hex(sha1));
 310        entry->converted = 1;
 311        free(buffer);
 312        free(data);
 313        return entry;
 314}
 315
 316int main(int argc, char **argv)
 317{
 318        unsigned char sha1[20];
 319        struct entry *entry;
 320
 321        if (argc != 2 || get_sha1(argv[1], sha1))
 322                usage("git-convert-objects <sha1>");
 323
 324        entry = convert_entry(sha1);
 325        printf("new sha1: %s\n", sha1_to_hex(entry->new_sha1));
 326        return 0;
 327}