Andrew's git - gitweb.git/blob - vcs-svn/fast

   1/*
   2 * Licensed under a two-clause BSD-style license.
   3 * See LICENSE for details.
   4 */
   5
   6#include "git-compat-util.h"
   7#include "strbuf.h"
   8#include "quote.h"
   9#include "fast_export.h"
  10#include "repo_tree.h"
  11#include "strbuf.h"
  12#include "svndiff.h"
  13#include "sliding_window.h"
  14#include "line_buffer.h"
  15
  16#define MAX_GITSVN_LINE_LEN 4096
  17
  18static uint32_t first_commit_done;
  19static struct line_buffer postimage = LINE_BUFFER_INIT;
  20static struct line_buffer report_buffer = LINE_BUFFER_INIT;
  21
  22/* NEEDSWORK: move to fast_export_init() */
  23static int init_postimage(void)
  24{
  25        static int postimage_initialized;
  26        if (postimage_initialized)
  27                return 0;
  28        postimage_initialized = 1;
  29        return buffer_tmpfile_init(&postimage);
  30}
  31
  32void fast_export_init(int fd)
  33{
  34        first_commit_done = 0;
  35        if (buffer_fdinit(&report_buffer, fd))
  36                die_errno("cannot read from file descriptor %d", fd);
  37}
  38
  39void fast_export_deinit(void)
  40{
  41        if (buffer_deinit(&report_buffer))
  42                die_errno("error closing fast-import feedback stream");
  43}
  44
  45void fast_export_delete(const char *path)
  46{
  47        putchar('D');
  48        putchar(' ');
  49        quote_c_style(path, NULL, stdout, 0);
  50        putchar('\n');
  51}
  52
  53static void fast_export_truncate(const char *path, uint32_t mode)
  54{
  55        fast_export_modify(path, mode, "inline");
  56        printf("data 0\n\n");
  57}
  58
  59void fast_export_modify(const char *path, uint32_t mode, const char *dataref)
  60{
  61        /* Mode must be 100644, 100755, 120000, or 160000. */
  62        if (!dataref) {
  63                fast_export_truncate(path, mode);
  64                return;
  65        }
  66        printf("M %06"PRIo32" %s ", mode, dataref);
  67        quote_c_style(path, NULL, stdout, 0);
  68        putchar('\n');
  69}
  70
  71static char gitsvnline[MAX_GITSVN_LINE_LEN];
  72void fast_export_begin_commit(uint32_t revision, const char *author,
  73                        const struct strbuf *log,
  74                        const char *uuid, const char *url,
  75                        unsigned long timestamp)
  76{
  77        static const struct strbuf empty = STRBUF_INIT;
  78        if (!log)
  79                log = &empty;
  80        if (*uuid && *url) {
  81                snprintf(gitsvnline, MAX_GITSVN_LINE_LEN,
  82                                "\n\ngit-svn-id: %s@%"PRIu32" %s\n",
  83                                 url, revision, uuid);
  84        } else {
  85                *gitsvnline = '\0';
  86        }
  87        printf("commit refs/heads/master\n");
  88        printf("mark :%"PRIu32"\n", revision);
  89        printf("committer %s <%s@%s> %ld +0000\n",
  90                   *author ? author : "nobody",
  91                   *author ? author : "nobody",
  92                   *uuid ? uuid : "local", timestamp);
  93        printf("data %"PRIuMAX"\n",
  94                (uintmax_t) (log->len + strlen(gitsvnline)));
  95        fwrite(log->buf, log->len, 1, stdout);
  96        printf("%s\n", gitsvnline);
  97        if (!first_commit_done) {
  98                if (revision > 1)
  99                        printf("from :%"PRIu32"\n", revision - 1);
 100                first_commit_done = 1;
 101        }
 102}
 103
 104void fast_export_end_commit(uint32_t revision)
 105{
 106        printf("progress Imported commit %"PRIu32".\n\n", revision);
 107}
 108
 109static void ls_from_rev(uint32_t rev, const char *path)
 110{
 111        /* ls :5 path/to/old/file */
 112        printf("ls :%"PRIu32" ", rev);
 113        quote_c_style(path, NULL, stdout, 0);
 114        putchar('\n');
 115        fflush(stdout);
 116}
 117
 118static void ls_from_active_commit(const char *path)
 119{
 120        /* ls "path/to/file" */
 121        printf("ls \"");
 122        quote_c_style(path, NULL, stdout, 1);
 123        printf("\"\n");
 124        fflush(stdout);
 125}
 126
 127static const char *get_response_line(void)
 128{
 129        const char *line = buffer_read_line(&report_buffer);
 130        if (line)
 131                return line;
 132        if (buffer_ferror(&report_buffer))
 133                die_errno("error reading from fast-import");
 134        die("unexpected end of fast-import feedback");
 135}
 136
 137static void die_short_read(struct line_buffer *input)
 138{
 139        if (buffer_ferror(input))
 140                die_errno("error reading dump file");
 141        die("invalid dump: unexpected end of file");
 142}
 143
 144static int ends_with(const char *s, size_t len, const char *suffix)
 145{
 146        const size_t suffixlen = strlen(suffix);
 147        if (len < suffixlen)
 148                return 0;
 149        return !memcmp(s + len - suffixlen, suffix, suffixlen);
 150}
 151
 152static int parse_cat_response_line(const char *header, off_t *len)
 153{
 154        size_t headerlen = strlen(header);
 155        uintmax_t n;
 156        const char *type;
 157        const char *end;
 158
 159        if (ends_with(header, headerlen, " missing"))
 160                return error("cat-blob reports missing blob: %s", header);
 161        type = strstr(header, " blob ");
 162        if (!type)
 163                return error("cat-blob header has wrong object type: %s", header);
 164        n = strtoumax(type + strlen(" blob "), (char **) &end, 10);
 165        if (end == type + strlen(" blob "))
 166                return error("cat-blob header does not contain length: %s", header);
 167        if (memchr(type + strlen(" blob "), '-', end - type - strlen(" blob ")))
 168                return error("cat-blob header contains negative length: %s", header);
 169        if (n == UINTMAX_MAX || n > maximum_signed_value_of_type(off_t))
 170                return error("blob too large for current definition of off_t");
 171        *len = n;
 172        if (*end)
 173                return error("cat-blob header contains garbage after length: %s", header);
 174        return 0;
 175}
 176
 177static void check_preimage_overflow(off_t a, off_t b)
 178{
 179        if (signed_add_overflows(a, b))
 180                die("blob too large for current definition of off_t");
 181}
 182
 183static long apply_delta(off_t len, struct line_buffer *input,
 184                        const char *old_data, uint32_t old_mode)
 185{
 186        long ret;
 187        struct sliding_view preimage = SLIDING_VIEW_INIT(&report_buffer, 0);
 188        FILE *out;
 189
 190        if (init_postimage() || !(out = buffer_tmpfile_rewind(&postimage)))
 191                die("cannot open temporary file for blob retrieval");
 192        if (old_data) {
 193                const char *response;
 194                printf("cat-blob %s\n", old_data);
 195                fflush(stdout);
 196                response = get_response_line();
 197                if (parse_cat_response_line(response, &preimage.max_off))
 198                        die("invalid cat-blob response: %s", response);
 199                check_preimage_overflow(preimage.max_off, 1);
 200        }
 201        if (old_mode == REPO_MODE_LNK) {
 202                strbuf_addstr(&preimage.buf, "link ");
 203                check_preimage_overflow(preimage.max_off, strlen("link "));
 204                preimage.max_off += strlen("link ");
 205                check_preimage_overflow(preimage.max_off, 1);
 206        }
 207        if (svndiff0_apply(input, len, &preimage, out))
 208                die("cannot apply delta");
 209        if (old_data) {
 210                /* Read the remainder of preimage and trailing newline. */
 211                assert(!signed_add_overflows(preimage.max_off, 1));
 212                preimage.max_off++;     /* room for newline */
 213                if (move_window(&preimage, preimage.max_off - 1, 1))
 214                        die("cannot seek to end of input");
 215                if (preimage.buf.buf[0] != '\n')
 216                        die("missing newline after cat-blob response");
 217        }
 218        ret = buffer_tmpfile_prepare_to_read(&postimage);
 219        if (ret < 0)
 220                die("cannot read temporary file for blob retrieval");
 221        strbuf_release(&preimage.buf);
 222        return ret;
 223}
 224
 225void fast_export_data(uint32_t mode, off_t len, struct line_buffer *input)
 226{
 227        assert(len >= 0);
 228        if (mode == REPO_MODE_LNK) {
 229                /* svn symlink blobs start with "link " */
 230                if (len < 5)
 231                        die("invalid dump: symlink too short for \"link\" prefix");
 232                len -= 5;
 233                if (buffer_skip_bytes(input, 5) != 5)
 234                        die_short_read(input);
 235        }
 236        printf("data %"PRIuMAX"\n", (uintmax_t) len);
 237        if (buffer_copy_bytes(input, len) != len)
 238                die_short_read(input);
 239        fputc('\n', stdout);
 240}
 241
 242static int parse_ls_response(const char *response, uint32_t *mode,
 243                                        struct strbuf *dataref)
 244{
 245        const char *tab;
 246        const char *response_end;
 247
 248        assert(response);
 249        response_end = response + strlen(response);
 250
 251        if (*response == 'm') { /* Missing. */
 252                errno = ENOENT;
 253                return -1;
 254        }
 255
 256        /* Mode. */
 257        if (response_end - response < (signed) strlen("100644") ||
 258            response[strlen("100644")] != ' ')
 259                die("invalid ls response: missing mode: %s", response);
 260        *mode = 0;
 261        for (; *response != ' '; response++) {
 262                char ch = *response;
 263                if (ch < '0' || ch > '7')
 264                        die("invalid ls response: mode is not octal: %s", response);
 265                *mode *= 8;
 266                *mode += ch - '0';
 267        }
 268
 269        /* ' blob ' or ' tree ' */
 270        if (response_end - response < (signed) strlen(" blob ") ||
 271            (response[1] != 'b' && response[1] != 't'))
 272                die("unexpected ls response: not a tree or blob: %s", response);
 273        response += strlen(" blob ");
 274
 275        /* Dataref. */
 276        tab = memchr(response, '\t', response_end - response);
 277        if (!tab)
 278                die("invalid ls response: missing tab: %s", response);
 279        strbuf_add(dataref, response, tab - response);
 280        return 0;
 281}
 282
 283int fast_export_ls_rev(uint32_t rev, const char *path,
 284                                uint32_t *mode, struct strbuf *dataref)
 285{
 286        ls_from_rev(rev, path);
 287        return parse_ls_response(get_response_line(), mode, dataref);
 288}
 289
 290int fast_export_ls(const char *path, uint32_t *mode, struct strbuf *dataref)
 291{
 292        ls_from_active_commit(path);
 293        return parse_ls_response(get_response_line(), mode, dataref);
 294}
 295
 296void fast_export_blob_delta(uint32_t mode,
 297                                uint32_t old_mode, const char *old_data,
 298                                off_t len, struct line_buffer *input)
 299{
 300        long postimage_len;
 301
 302        assert(len >= 0);
 303        postimage_len = apply_delta(len, input, old_data, old_mode);
 304        if (mode == REPO_MODE_LNK) {
 305                buffer_skip_bytes(&postimage, strlen("link "));
 306                postimage_len -= strlen("link ");
 307        }
 308        printf("data %ld\n", postimage_len);
 309        buffer_copy_bytes(&postimage, postimage_len);
 310        fputc('\n', stdout);
 311}