convert-objects.con commit Merge git://git.kernel.org/pub/scm/gitk/gitk (d69dc37)
   1#define _XOPEN_SOURCE 500 /* glibc2 and AIX 5.3L need this */
   2#define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
   3#include <time.h>
   4#include "cache.h"
   5#include "blob.h"
   6#include "commit.h"
   7#include "tree.h"
   8
   9struct entry {
  10        unsigned char old_sha1[20];
  11        unsigned char new_sha1[20];
  12        int converted;
  13};
  14
  15#define MAXOBJECTS (1000000)
  16
  17static struct entry *convert[MAXOBJECTS];
  18static int nr_convert;
  19
  20static struct entry * convert_entry(unsigned char *sha1);
  21
  22static struct entry *insert_new(unsigned char *sha1, int pos)
  23{
  24        struct entry *new = xcalloc(1, sizeof(struct entry));
  25        memcpy(new->old_sha1, sha1, 20);
  26        memmove(convert + pos + 1, convert + pos, (nr_convert - pos) * sizeof(struct entry *));
  27        convert[pos] = new;
  28        nr_convert++;
  29        if (nr_convert == MAXOBJECTS)
  30                die("you're kidding me - hit maximum object limit");
  31        return new;
  32}
  33
  34static struct entry *lookup_entry(unsigned char *sha1)
  35{
  36        int low = 0, high = nr_convert;
  37
  38        while (low < high) {
  39                int next = (low + high) / 2;
  40                struct entry *n = convert[next];
  41                int cmp = memcmp(sha1, n->old_sha1, 20);
  42                if (!cmp)
  43                        return n;
  44                if (cmp < 0) {
  45                        high = next;
  46                        continue;
  47                }
  48                low = next+1;
  49        }
  50        return insert_new(sha1, low);
  51}
  52
  53static void convert_binary_sha1(void *buffer)
  54{
  55        struct entry *entry = convert_entry(buffer);
  56        memcpy(buffer, entry->new_sha1, 20);
  57}
  58
  59static void convert_ascii_sha1(void *buffer)
  60{
  61        unsigned char sha1[20];
  62        struct entry *entry;
  63
  64        if (get_sha1_hex(buffer, sha1))
  65                die("expected sha1, got '%s'", (char*) buffer);
  66        entry = convert_entry(sha1);
  67        memcpy(buffer, sha1_to_hex(entry->new_sha1), 40);
  68}
  69
  70static unsigned int convert_mode(unsigned int mode)
  71{
  72        unsigned int newmode;
  73
  74        newmode = mode & S_IFMT;
  75        if (S_ISREG(mode))
  76                newmode |= (mode & 0100) ? 0755 : 0644;
  77        return newmode;
  78}
  79
  80static int write_subdirectory(void *buffer, unsigned long size, const char *base, int baselen, unsigned char *result_sha1)
  81{
  82        char *new = xmalloc(size);
  83        unsigned long newlen = 0;
  84        unsigned long used;
  85
  86        used = 0;
  87        while (size) {
  88                int len = 21 + strlen(buffer);
  89                char *path = strchr(buffer, ' ');
  90                unsigned char *sha1;
  91                unsigned int mode;
  92                char *slash, *origpath;
  93
  94                if (!path || sscanf(buffer, "%o", &mode) != 1)
  95                        die("bad tree conversion");
  96                mode = convert_mode(mode);
  97                path++;
  98                if (memcmp(path, base, baselen))
  99                        break;
 100                origpath = path;
 101                path += baselen;
 102                slash = strchr(path, '/');
 103                if (!slash) {
 104                        newlen += sprintf(new + newlen, "%o %s", mode, path);
 105                        new[newlen++] = '\0';
 106                        memcpy(new + newlen, buffer + len - 20, 20);
 107                        newlen += 20;
 108
 109                        used += len;
 110                        size -= len;
 111                        buffer += len;
 112                        continue;
 113                }
 114
 115                newlen += sprintf(new + newlen, "%o %.*s", S_IFDIR, (int)(slash - path), path);
 116                new[newlen++] = 0;
 117                sha1 = (unsigned char *)(new + newlen);
 118                newlen += 20;
 119
 120                len = write_subdirectory(buffer, size, origpath, slash-origpath+1, sha1);
 121
 122                used += len;
 123                size -= len;
 124                buffer += len;
 125        }
 126
 127        write_sha1_file(new, newlen, tree_type, result_sha1);
 128        free(new);
 129        return used;
 130}
 131
 132static void convert_tree(void *buffer, unsigned long size, unsigned char *result_sha1)
 133{
 134        void *orig_buffer = buffer;
 135        unsigned long orig_size = size;
 136
 137        while (size) {
 138                int len = 1+strlen(buffer);
 139
 140                convert_binary_sha1(buffer + len);
 141
 142                len += 20;
 143                if (len > size)
 144                        die("corrupt tree object");
 145                size -= len;
 146                buffer += len;
 147        }
 148
 149        write_subdirectory(orig_buffer, orig_size, "", 0, result_sha1);
 150}
 151
 152static unsigned long parse_oldstyle_date(const char *buf)
 153{
 154        char c, *p;
 155        char buffer[100];
 156        struct tm tm;
 157        const char *formats[] = {
 158                "%c",
 159                "%a %b %d %T",
 160                "%Z",
 161                "%Y",
 162                " %Y",
 163                NULL
 164        };
 165        /* We only ever did two timezones in the bad old format .. */
 166        const char *timezones[] = {
 167                "PDT", "PST", "CEST", NULL
 168        };
 169        const char **fmt = formats;
 170
 171        p = buffer;
 172        while (isspace(c = *buf))
 173                buf++;
 174        while ((c = *buf++) != '\n')
 175                *p++ = c;
 176        *p++ = 0;
 177        buf = buffer;
 178        memset(&tm, 0, sizeof(tm));
 179        do {
 180                const char *next = strptime(buf, *fmt, &tm);
 181                if (next) {
 182                        if (!*next)
 183                                return mktime(&tm);
 184                        buf = next;
 185                } else {
 186                        const char **p = timezones;
 187                        while (isspace(*buf))
 188                                buf++;
 189                        while (*p) {
 190                                if (!memcmp(buf, *p, strlen(*p))) {
 191                                        buf += strlen(*p);
 192                                        break;
 193                                }
 194                                p++;
 195                        }
 196                }
 197                fmt++;
 198        } while (*buf && *fmt);
 199        printf("left: %s\n", buf);
 200        return mktime(&tm);                             
 201}
 202
 203static int convert_date_line(char *dst, void **buf, unsigned long *sp)
 204{
 205        unsigned long size = *sp;
 206        char *line = *buf;
 207        char *next = strchr(line, '\n');
 208        char *date = strchr(line, '>');
 209        int len;
 210
 211        if (!next || !date)
 212                die("missing or bad author/committer line %s", line);
 213        next++; date += 2;
 214
 215        *buf = next;
 216        *sp = size - (next - line);
 217
 218        len = date - line;
 219        memcpy(dst, line, len);
 220        dst += len;
 221
 222        /* Is it already in new format? */
 223        if (isdigit(*date)) {
 224                int datelen = next - date;
 225                memcpy(dst, date, datelen);
 226                return len + datelen;
 227        }
 228
 229        /*
 230         * Hacky hacky: one of the sparse old-style commits does not have
 231         * any date at all, but we can fake it by using the committer date.
 232         */
 233        if (*date == '\n' && strchr(next, '>'))
 234                date = strchr(next, '>')+2;
 235
 236        return len + sprintf(dst, "%lu -0700\n", parse_oldstyle_date(date));
 237}
 238
 239static void convert_date(void *buffer, unsigned long size, unsigned char *result_sha1)
 240{
 241        char *new = xmalloc(size + 100);
 242        unsigned long newlen = 0;
 243        
 244        // "tree <sha1>\n"
 245        memcpy(new + newlen, buffer, 46);
 246        newlen += 46;
 247        buffer += 46;
 248        size -= 46;
 249
 250        // "parent <sha1>\n"
 251        while (!memcmp(buffer, "parent ", 7)) {
 252                memcpy(new + newlen, buffer, 48);
 253                newlen += 48;
 254                buffer += 48;
 255                size -= 48;
 256        }
 257
 258        // "author xyz <xyz> date"
 259        newlen += convert_date_line(new + newlen, &buffer, &size);
 260        // "committer xyz <xyz> date"
 261        newlen += convert_date_line(new + newlen, &buffer, &size);
 262
 263        // Rest
 264        memcpy(new + newlen, buffer, size);
 265        newlen += size;
 266
 267        write_sha1_file(new, newlen, commit_type, result_sha1);
 268        free(new);
 269}
 270
 271static void convert_commit(void *buffer, unsigned long size, unsigned char *result_sha1)
 272{
 273        void *orig_buffer = buffer;
 274        unsigned long orig_size = size;
 275
 276        if (memcmp(buffer, "tree ", 5))
 277                die("Bad commit '%s'", (char*) buffer);
 278        convert_ascii_sha1(buffer+5);
 279        buffer += 46;    /* "tree " + "hex sha1" + "\n" */
 280        while (!memcmp(buffer, "parent ", 7)) {
 281                convert_ascii_sha1(buffer+7);
 282                buffer += 48;
 283        }
 284        convert_date(orig_buffer, orig_size, result_sha1);
 285}
 286
 287static struct entry * convert_entry(unsigned char *sha1)
 288{
 289        struct entry *entry = lookup_entry(sha1);
 290        char type[20];
 291        void *buffer, *data;
 292        unsigned long size;
 293
 294        if (entry->converted)
 295                return entry;
 296        data = read_sha1_file(sha1, type, &size);
 297        if (!data)
 298                die("unable to read object %s", sha1_to_hex(sha1));
 299
 300        buffer = xmalloc(size);
 301        memcpy(buffer, data, size);
 302
 303        if (!strcmp(type, blob_type)) {
 304                write_sha1_file(buffer, size, blob_type, entry->new_sha1);
 305        } else if (!strcmp(type, tree_type))
 306                convert_tree(buffer, size, entry->new_sha1);
 307        else if (!strcmp(type, commit_type))
 308                convert_commit(buffer, size, entry->new_sha1);
 309        else
 310                die("unknown object type '%s' in %s", type, sha1_to_hex(sha1));
 311        entry->converted = 1;
 312        free(buffer);
 313        free(data);
 314        return entry;
 315}
 316
 317int main(int argc, char **argv)
 318{
 319        unsigned char sha1[20];
 320        struct entry *entry;
 321
 322        setup_git_directory();
 323
 324        if (argc != 2 || get_sha1(argv[1], sha1))
 325                usage("git-convert-objects <sha1>");
 326
 327        entry = convert_entry(sha1);
 328        printf("new sha1: %s\n", sha1_to_hex(entry->new_sha1));
 329        return 0;
 330}