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#define REPORT_FILENO 3
  18
  19static uint32_t first_commit_done;
  20static struct line_buffer postimage = LINE_BUFFER_INIT;
  21static struct line_buffer report_buffer = LINE_BUFFER_INIT;
  22
  23/* NEEDSWORK: move to fast_export_init() */
  24static int init_postimage(void)
  25{
  26        static int postimage_initialized;
  27        if (postimage_initialized)
  28                return 0;
  29        postimage_initialized = 1;
  30        return buffer_tmpfile_init(&postimage);
  31}
  32
  33static int init_report_buffer(int fd)
  34{
  35        static int report_buffer_initialized;
  36        if (report_buffer_initialized)
  37                return 0;
  38        report_buffer_initialized = 1;
  39        return buffer_fdinit(&report_buffer, fd);
  40}
  41
  42void fast_export_init(int fd)
  43{
  44        if (buffer_fdinit(&report_buffer, fd))
  45                die_errno("cannot read from file descriptor %d", fd);
  46}
  47
  48void fast_export_deinit(void)
  49{
  50        if (buffer_deinit(&report_buffer))
  51                die_errno("error closing fast-import feedback stream");
  52}
  53
  54void fast_export_reset(void)
  55{
  56        buffer_reset(&report_buffer);
  57}
  58
  59void fast_export_delete(const char *path)
  60{
  61        putchar('D');
  62        putchar(' ');
  63        quote_c_style(path, NULL, stdout, 0);
  64        putchar('\n');
  65}
  66
  67static void fast_export_truncate(const char *path, uint32_t mode)
  68{
  69        fast_export_modify(path, mode, "inline");
  70        printf("data 0\n\n");
  71}
  72
  73void fast_export_modify(const char *path, uint32_t mode, const char *dataref)
  74{
  75        /* Mode must be 100644, 100755, 120000, or 160000. */
  76        if (!dataref) {
  77                fast_export_truncate(path, mode);
  78                return;
  79        }
  80        printf("M %06"PRIo32" %s ", mode, dataref);
  81        quote_c_style(path, NULL, stdout, 0);
  82        putchar('\n');
  83}
  84
  85static char gitsvnline[MAX_GITSVN_LINE_LEN];
  86void fast_export_begin_commit(uint32_t revision, const char *author,
  87                        const struct strbuf *log,
  88                        const char *uuid, const char *url,
  89                        unsigned long timestamp)
  90{
  91        static const struct strbuf empty = STRBUF_INIT;
  92        if (!log)
  93                log = &empty;
  94        if (*uuid && *url) {
  95                snprintf(gitsvnline, MAX_GITSVN_LINE_LEN,
  96                                "\n\ngit-svn-id: %s@%"PRIu32" %s\n",
  97                                 url, revision, uuid);
  98        } else {
  99                *gitsvnline = '\0';
 100        }
 101        printf("commit refs/heads/master\n");
 102        printf("mark :%"PRIu32"\n", revision);
 103        printf("committer %s <%s@%s> %ld +0000\n",
 104                   *author ? author : "nobody",
 105                   *author ? author : "nobody",
 106                   *uuid ? uuid : "local", timestamp);
 107        printf("data %"PRIuMAX"\n",
 108                (uintmax_t) (log->len + strlen(gitsvnline)));
 109        fwrite(log->buf, log->len, 1, stdout);
 110        printf("%s\n", gitsvnline);
 111        if (!first_commit_done) {
 112                if (revision > 1)
 113                        printf("from :%"PRIu32"\n", revision - 1);
 114                first_commit_done = 1;
 115        }
 116}
 117
 118void fast_export_end_commit(uint32_t revision)
 119{
 120        printf("progress Imported commit %"PRIu32".\n\n", revision);
 121}
 122
 123static void ls_from_rev(uint32_t rev, const char *path)
 124{
 125        /* ls :5 path/to/old/file */
 126        printf("ls :%"PRIu32" ", rev);
 127        quote_c_style(path, NULL, stdout, 0);
 128        putchar('\n');
 129        fflush(stdout);
 130}
 131
 132static void ls_from_active_commit(const char *path)
 133{
 134        /* ls "path/to/file" */
 135        printf("ls \"");
 136        quote_c_style(path, NULL, stdout, 1);
 137        printf("\"\n");
 138        fflush(stdout);
 139}
 140
 141static const char *get_response_line(void)
 142{
 143        const char *line = buffer_read_line(&report_buffer);
 144        if (line)
 145                return line;
 146        if (buffer_ferror(&report_buffer))
 147                die_errno("error reading from fast-import");
 148        die("unexpected end of fast-import feedback");
 149}
 150
 151static void die_short_read(struct line_buffer *input)
 152{
 153        if (buffer_ferror(input))
 154                die_errno("error reading dump file");
 155        die("invalid dump: unexpected end of file");
 156}
 157
 158static int ends_with(const char *s, size_t len, const char *suffix)
 159{
 160        const size_t suffixlen = strlen(suffix);
 161        if (len < suffixlen)
 162                return 0;
 163        return !memcmp(s + len - suffixlen, suffix, suffixlen);
 164}
 165
 166static int parse_cat_response_line(const char *header, off_t *len)
 167{
 168        size_t headerlen = strlen(header);
 169        uintmax_t n;
 170        const char *type;
 171        const char *end;
 172
 173        if (ends_with(header, headerlen, " missing"))
 174                return error("cat-blob reports missing blob: %s", header);
 175        type = memmem(header, headerlen, " blob ", strlen(" blob "));
 176        if (!type)
 177                return error("cat-blob header has wrong object type: %s", header);
 178        n = strtoumax(type + strlen(" blob "), (char **) &end, 10);
 179        if (end == type + strlen(" blob "))
 180                return error("cat-blob header does not contain length: %s", header);
 181        if (memchr(type + strlen(" blob "), '-', end - type - strlen(" blob ")))
 182                return error("cat-blob header contains negative length: %s", header);
 183        if (n == UINTMAX_MAX || n > maximum_signed_value_of_type(off_t))
 184                return error("blob too large for current definition of off_t");
 185        *len = n;
 186        if (*end)
 187                return error("cat-blob header contains garbage after length: %s", header);
 188        return 0;
 189}
 190
 191static void check_preimage_overflow(off_t a, off_t b)
 192{
 193        if (signed_add_overflows(a, b))
 194                die("blob too large for current definition of off_t");
 195}
 196
 197static long apply_delta(off_t len, struct line_buffer *input,
 198                        const char *old_data, uint32_t old_mode)
 199{
 200        long ret;
 201        struct sliding_view preimage = SLIDING_VIEW_INIT(&report_buffer, 0);
 202        FILE *out;
 203
 204        if (init_postimage() || !(out = buffer_tmpfile_rewind(&postimage)))
 205                die("cannot open temporary file for blob retrieval");
 206        if (init_report_buffer(REPORT_FILENO))
 207                die("cannot open fd 3 for feedback from fast-import");
 208        if (old_data) {
 209                const char *response;
 210                printf("cat-blob %s\n", old_data);
 211                fflush(stdout);
 212                response = get_response_line();
 213                if (parse_cat_response_line(response, &preimage.max_off))
 214                        die("invalid cat-blob response: %s", response);
 215                check_preimage_overflow(preimage.max_off, 1);
 216        }
 217        if (old_mode == REPO_MODE_LNK) {
 218                strbuf_addstr(&preimage.buf, "link ");
 219                check_preimage_overflow(preimage.max_off, strlen("link "));
 220                preimage.max_off += strlen("link ");
 221                check_preimage_overflow(preimage.max_off, 1);
 222        }
 223        if (svndiff0_apply(input, len, &preimage, out))
 224                die("cannot apply delta");
 225        if (old_data) {
 226                /* Read the remainder of preimage and trailing newline. */
 227                assert(!signed_add_overflows(preimage.max_off, 1));
 228                preimage.max_off++;     /* room for newline */
 229                if (move_window(&preimage, preimage.max_off - 1, 1))
 230                        die("cannot seek to end of input");
 231                if (preimage.buf.buf[0] != '\n')
 232                        die("missing newline after cat-blob response");
 233        }
 234        ret = buffer_tmpfile_prepare_to_read(&postimage);
 235        if (ret < 0)
 236                die("cannot read temporary file for blob retrieval");
 237        strbuf_release(&preimage.buf);
 238        return ret;
 239}
 240
 241void fast_export_data(uint32_t mode, uint32_t len, struct line_buffer *input)
 242{
 243        if (mode == REPO_MODE_LNK) {
 244                /* svn symlink blobs start with "link " */
 245                len -= 5;
 246                if (buffer_skip_bytes(input, 5) != 5)
 247                        die_short_read(input);
 248        }
 249        printf("data %"PRIu32"\n", len);
 250        if (buffer_copy_bytes(input, len) != len)
 251                die_short_read(input);
 252        fputc('\n', stdout);
 253}
 254
 255static int parse_ls_response(const char *response, uint32_t *mode,
 256                                        struct strbuf *dataref)
 257{
 258        const char *tab;
 259        const char *response_end;
 260
 261        assert(response);
 262        response_end = response + strlen(response);
 263
 264        if (*response == 'm') { /* Missing. */
 265                errno = ENOENT;
 266                return -1;
 267        }
 268
 269        /* Mode. */
 270        if (response_end - response < strlen("100644") ||
 271            response[strlen("100644")] != ' ')
 272                die("invalid ls response: missing mode: %s", response);
 273        *mode = 0;
 274        for (; *response != ' '; response++) {
 275                char ch = *response;
 276                if (ch < '0' || ch > '7')
 277                        die("invalid ls response: mode is not octal: %s", response);
 278                *mode *= 8;
 279                *mode += ch - '0';
 280        }
 281
 282        /* ' blob ' or ' tree ' */
 283        if (response_end - response < strlen(" blob ") ||
 284            (response[1] != 'b' && response[1] != 't'))
 285                die("unexpected ls response: not a tree or blob: %s", response);
 286        response += strlen(" blob ");
 287
 288        /* Dataref. */
 289        tab = memchr(response, '\t', response_end - response);
 290        if (!tab)
 291                die("invalid ls response: missing tab: %s", response);
 292        strbuf_add(dataref, response, tab - response);
 293        return 0;
 294}
 295
 296int fast_export_ls_rev(uint32_t rev, const char *path,
 297                                uint32_t *mode, struct strbuf *dataref)
 298{
 299        ls_from_rev(rev, path);
 300        return parse_ls_response(get_response_line(), mode, dataref);
 301}
 302
 303int fast_export_ls(const char *path, uint32_t *mode, struct strbuf *dataref)
 304{
 305        ls_from_active_commit(path);
 306        return parse_ls_response(get_response_line(), mode, dataref);
 307}
 308
 309void fast_export_blob_delta(uint32_t mode,
 310                                uint32_t old_mode, const char *old_data,
 311                                uint32_t len, struct line_buffer *input)
 312{
 313        long postimage_len;
 314        if (len > maximum_signed_value_of_type(off_t))
 315                die("enormous delta");
 316        postimage_len = apply_delta((off_t) len, input, old_data, old_mode);
 317        if (mode == REPO_MODE_LNK) {
 318                buffer_skip_bytes(&postimage, strlen("link "));
 319                postimage_len -= strlen("link ");
 320        }
 321        printf("data %ld\n", postimage_len);
 322        buffer_copy_bytes(&postimage, postimage_len);
 323        fputc('\n', stdout);
 324}