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_reset(void)
  46{
  47        buffer_reset(&report_buffer);
  48}
  49
  50void fast_export_delete(const char *path)
  51{
  52        putchar('D');
  53        putchar(' ');
  54        quote_c_style(path, NULL, stdout, 0);
  55        putchar('\n');
  56}
  57
  58static void fast_export_truncate(const char *path, uint32_t mode)
  59{
  60        fast_export_modify(path, mode, "inline");
  61        printf("data 0\n\n");
  62}
  63
  64void fast_export_modify(const char *path, uint32_t mode, const char *dataref)
  65{
  66        /* Mode must be 100644, 100755, 120000, or 160000. */
  67        if (!dataref) {
  68                fast_export_truncate(path, mode);
  69                return;
  70        }
  71        printf("M %06"PRIo32" %s ", mode, dataref);
  72        quote_c_style(path, NULL, stdout, 0);
  73        putchar('\n');
  74}
  75
  76static char gitsvnline[MAX_GITSVN_LINE_LEN];
  77void fast_export_begin_commit(uint32_t revision, const char *author,
  78                        const struct strbuf *log,
  79                        const char *uuid, const char *url,
  80                        unsigned long timestamp)
  81{
  82        static const struct strbuf empty = STRBUF_INIT;
  83        if (!log)
  84                log = &empty;
  85        if (*uuid && *url) {
  86                snprintf(gitsvnline, MAX_GITSVN_LINE_LEN,
  87                                "\n\ngit-svn-id: %s@%"PRIu32" %s\n",
  88                                 url, revision, uuid);
  89        } else {
  90                *gitsvnline = '\0';
  91        }
  92        printf("commit refs/heads/master\n");
  93        printf("mark :%"PRIu32"\n", revision);
  94        printf("committer %s <%s@%s> %ld +0000\n",
  95                   *author ? author : "nobody",
  96                   *author ? author : "nobody",
  97                   *uuid ? uuid : "local", timestamp);
  98        printf("data %"PRIuMAX"\n",
  99                (uintmax_t) (log->len + strlen(gitsvnline)));
 100        fwrite(log->buf, log->len, 1, stdout);
 101        printf("%s\n", gitsvnline);
 102        if (!first_commit_done) {
 103                if (revision > 1)
 104                        printf("from :%"PRIu32"\n", revision - 1);
 105                first_commit_done = 1;
 106        }
 107}
 108
 109void fast_export_end_commit(uint32_t revision)
 110{
 111        printf("progress Imported commit %"PRIu32".\n\n", revision);
 112}
 113
 114static void ls_from_rev(uint32_t rev, const char *path)
 115{
 116        /* ls :5 path/to/old/file */
 117        printf("ls :%"PRIu32" ", rev);
 118        quote_c_style(path, NULL, stdout, 0);
 119        putchar('\n');
 120        fflush(stdout);
 121}
 122
 123static void ls_from_active_commit(const char *path)
 124{
 125        /* ls "path/to/file" */
 126        printf("ls \"");
 127        quote_c_style(path, NULL, stdout, 1);
 128        printf("\"\n");
 129        fflush(stdout);
 130}
 131
 132static const char *get_response_line(void)
 133{
 134        const char *line = buffer_read_line(&report_buffer);
 135        if (line)
 136                return line;
 137        if (buffer_ferror(&report_buffer))
 138                die_errno("error reading from fast-import");
 139        die("unexpected end of fast-import feedback");
 140}
 141
 142static void die_short_read(struct line_buffer *input)
 143{
 144        if (buffer_ferror(input))
 145                die_errno("error reading dump file");
 146        die("invalid dump: unexpected end of file");
 147}
 148
 149static int ends_with(const char *s, size_t len, const char *suffix)
 150{
 151        const size_t suffixlen = strlen(suffix);
 152        if (len < suffixlen)
 153                return 0;
 154        return !memcmp(s + len - suffixlen, suffix, suffixlen);
 155}
 156
 157static int parse_cat_response_line(const char *header, off_t *len)
 158{
 159        size_t headerlen = strlen(header);
 160        uintmax_t n;
 161        const char *type;
 162        const char *end;
 163
 164        if (ends_with(header, headerlen, " missing"))
 165                return error("cat-blob reports missing blob: %s", header);
 166        type = memmem(header, headerlen, " blob ", strlen(" blob "));
 167        if (!type)
 168                return error("cat-blob header has wrong object type: %s", header);
 169        n = strtoumax(type + strlen(" blob "), (char **) &end, 10);
 170        if (end == type + strlen(" blob "))
 171                return error("cat-blob header does not contain length: %s", header);
 172        if (memchr(type + strlen(" blob "), '-', end - type - strlen(" blob ")))
 173                return error("cat-blob header contains negative length: %s", header);
 174        if (n == UINTMAX_MAX || n > maximum_signed_value_of_type(off_t))
 175                return error("blob too large for current definition of off_t");
 176        *len = n;
 177        if (*end)
 178                return error("cat-blob header contains garbage after length: %s", header);
 179        return 0;
 180}
 181
 182static void check_preimage_overflow(off_t a, off_t b)
 183{
 184        if (signed_add_overflows(a, b))
 185                die("blob too large for current definition of off_t");
 186}
 187
 188static long apply_delta(off_t len, struct line_buffer *input,
 189                        const char *old_data, uint32_t old_mode)
 190{
 191        long ret;
 192        struct sliding_view preimage = SLIDING_VIEW_INIT(&report_buffer, 0);
 193        FILE *out;
 194
 195        if (init_postimage() || !(out = buffer_tmpfile_rewind(&postimage)))
 196                die("cannot open temporary file for blob retrieval");
 197        if (old_data) {
 198                const char *response;
 199                printf("cat-blob %s\n", old_data);
 200                fflush(stdout);
 201                response = get_response_line();
 202                if (parse_cat_response_line(response, &preimage.max_off))
 203                        die("invalid cat-blob response: %s", response);
 204                check_preimage_overflow(preimage.max_off, 1);
 205        }
 206        if (old_mode == REPO_MODE_LNK) {
 207                strbuf_addstr(&preimage.buf, "link ");
 208                check_preimage_overflow(preimage.max_off, strlen("link "));
 209                preimage.max_off += strlen("link ");
 210                check_preimage_overflow(preimage.max_off, 1);
 211        }
 212        if (svndiff0_apply(input, len, &preimage, out))
 213                die("cannot apply delta");
 214        if (old_data) {
 215                /* Read the remainder of preimage and trailing newline. */
 216                assert(!signed_add_overflows(preimage.max_off, 1));
 217                preimage.max_off++;     /* room for newline */
 218                if (move_window(&preimage, preimage.max_off - 1, 1))
 219                        die("cannot seek to end of input");
 220                if (preimage.buf.buf[0] != '\n')
 221                        die("missing newline after cat-blob response");
 222        }
 223        ret = buffer_tmpfile_prepare_to_read(&postimage);
 224        if (ret < 0)
 225                die("cannot read temporary file for blob retrieval");
 226        strbuf_release(&preimage.buf);
 227        return ret;
 228}
 229
 230void fast_export_data(uint32_t mode, off_t len, struct line_buffer *input)
 231{
 232        assert(len >= 0);
 233        if (mode == REPO_MODE_LNK) {
 234                /* svn symlink blobs start with "link " */
 235                if (len < 5)
 236                        die("invalid dump: symlink too short for \"link\" prefix");
 237                len -= 5;
 238                if (buffer_skip_bytes(input, 5) != 5)
 239                        die_short_read(input);
 240        }
 241        printf("data %"PRIuMAX"\n", (uintmax_t) len);
 242        if (buffer_copy_bytes(input, len) != len)
 243                die_short_read(input);
 244        fputc('\n', stdout);
 245}
 246
 247static int parse_ls_response(const char *response, uint32_t *mode,
 248                                        struct strbuf *dataref)
 249{
 250        const char *tab;
 251        const char *response_end;
 252
 253        assert(response);
 254        response_end = response + strlen(response);
 255
 256        if (*response == 'm') { /* Missing. */
 257                errno = ENOENT;
 258                return -1;
 259        }
 260
 261        /* Mode. */
 262        if (response_end - response < strlen("100644") ||
 263            response[strlen("100644")] != ' ')
 264                die("invalid ls response: missing mode: %s", response);
 265        *mode = 0;
 266        for (; *response != ' '; response++) {
 267                char ch = *response;
 268                if (ch < '0' || ch > '7')
 269                        die("invalid ls response: mode is not octal: %s", response);
 270                *mode *= 8;
 271                *mode += ch - '0';
 272        }
 273
 274        /* ' blob ' or ' tree ' */
 275        if (response_end - response < strlen(" blob ") ||
 276            (response[1] != 'b' && response[1] != 't'))
 277                die("unexpected ls response: not a tree or blob: %s", response);
 278        response += strlen(" blob ");
 279
 280        /* Dataref. */
 281        tab = memchr(response, '\t', response_end - response);
 282        if (!tab)
 283                die("invalid ls response: missing tab: %s", response);
 284        strbuf_add(dataref, response, tab - response);
 285        return 0;
 286}
 287
 288int fast_export_ls_rev(uint32_t rev, const char *path,
 289                                uint32_t *mode, struct strbuf *dataref)
 290{
 291        ls_from_rev(rev, path);
 292        return parse_ls_response(get_response_line(), mode, dataref);
 293}
 294
 295int fast_export_ls(const char *path, uint32_t *mode, struct strbuf *dataref)
 296{
 297        ls_from_active_commit(path);
 298        return parse_ls_response(get_response_line(), mode, dataref);
 299}
 300
 301void fast_export_blob_delta(uint32_t mode,
 302                                uint32_t old_mode, const char *old_data,
 303                                off_t len, struct line_buffer *input)
 304{
 305        long postimage_len;
 306
 307        assert(len >= 0);
 308        postimage_len = apply_delta(len, input, old_data, old_mode);
 309        if (mode == REPO_MODE_LNK) {
 310                buffer_skip_bytes(&postimage, strlen("link "));
 311                postimage_len -= strlen("link ");
 312        }
 313        printf("data %ld\n", postimage_len);
 314        buffer_copy_bytes(&postimage, postimage_len);
 315        fputc('\n', stdout);
 316}