mailinfo.con commit Flatten tools/ directory to make build procedure simpler. (597c9cc)
   1/*
   2 * Another stupid program, this one parsing the headers of an
   3 * email to figure out authorship and subject
   4 */
   5#define _GNU_SOURCE
   6#include <stdio.h>
   7#include <stdlib.h>
   8#include <string.h>
   9#include <ctype.h>
  10#include <iconv.h>
  11
  12static FILE *cmitmsg, *patchfile;
  13
  14static int keep_subject = 0;
  15static int metainfo_utf8 = 0;
  16static char line[1000];
  17static char date[1000];
  18static char name[1000];
  19static char email[1000];
  20static char subject[1000];
  21
  22static enum  {
  23        TE_DONTCARE, TE_QP, TE_BASE64,
  24} transfer_encoding;
  25static char charset[256];
  26
  27static char multipart_boundary[1000];
  28static int multipart_boundary_len;
  29static int patch_lines = 0;
  30
  31static char *sanity_check(char *name, char *email)
  32{
  33        int len = strlen(name);
  34        if (len < 3 || len > 60)
  35                return email;
  36        if (strchr(name, '@') || strchr(name, '<') || strchr(name, '>'))
  37                return email;
  38        return name;
  39}
  40
  41static int handle_from(char *line)
  42{
  43        char *at = strchr(line, '@');
  44        char *dst;
  45
  46        if (!at)
  47                return 0;
  48
  49        /*
  50         * If we already have one email, don't take any confusing lines
  51         */
  52        if (*email && strchr(at+1, '@'))
  53                return 0;
  54
  55        /* Pick up the string around '@', possibly delimited with <>
  56         * pair; that is the email part.  White them out while copying.
  57         */
  58        while (at > line) {
  59                char c = at[-1];
  60                if (isspace(c))
  61                        break;
  62                if (c == '<') {
  63                        at[-1] = ' ';
  64                        break;
  65                }
  66                at--;
  67        }
  68        dst = email;
  69        for (;;) {
  70                unsigned char c = *at;
  71                if (!c || c == '>' || isspace(c)) {
  72                        if (c == '>')
  73                                *at = ' ';
  74                        break;
  75                }
  76                *at++ = ' ';
  77                *dst++ = c;
  78        }
  79        *dst++ = 0;
  80
  81        /* The remainder is name.  It could be "John Doe <john.doe@xz>"
  82         * or "john.doe@xz (John Doe)", but we have whited out the
  83         * email part, so trim from both ends, possibly removing
  84         * the () pair at the end.
  85         */
  86        at = line + strlen(line);
  87        while (at > line) {
  88                unsigned char c = *--at;
  89                if (!isspace(c)) {
  90                        at[(c == ')') ? 0 : 1] = 0;
  91                        break;
  92                }
  93        }
  94
  95        at = line;
  96        for (;;) {
  97                unsigned char c = *at;
  98                if (!c || !isspace(c)) {
  99                        if (c == '(')
 100                                at++;
 101                        break;
 102                }
 103                at++;
 104        }
 105        at = sanity_check(at, email);
 106        strcpy(name, at);
 107        return 1;
 108}
 109
 110static int handle_date(char *line)
 111{
 112        strcpy(date, line);
 113        return 0;
 114}
 115
 116static int handle_subject(char *line)
 117{
 118        strcpy(subject, line);
 119        return 0;
 120}
 121
 122/* NOTE NOTE NOTE.  We do not claim we do full MIME.  We just attempt
 123 * to have enough heuristics to grok MIME encoded patches often found
 124 * on our mailing lists.  For example, we do not even treat header lines
 125 * case insensitively.
 126 */
 127
 128static int slurp_attr(const char *line, const char *name, char *attr)
 129{
 130        char *ends, *ap = strcasestr(line, name);
 131        size_t sz;
 132
 133        if (!ap) {
 134                *attr = 0;
 135                return 0;
 136        }
 137        ap += strlen(name);
 138        if (*ap == '"') {
 139                ap++;
 140                ends = "\"";
 141        }
 142        else
 143                ends = "; \t";
 144        sz = strcspn(ap, ends);
 145        memcpy(attr, ap, sz);
 146        attr[sz] = 0;
 147        return 1;
 148}
 149
 150static int handle_subcontent_type(char *line)
 151{
 152        /* We do not want to mess with boundary.  Note that we do not
 153         * handle nested multipart.
 154         */
 155        if (strcasestr(line, "boundary=")) {
 156                fprintf(stderr, "Not handling nested multipart message.\n");
 157                exit(1);
 158        }
 159        slurp_attr(line, "charset=", charset);
 160        if (*charset) {
 161                int i, c;
 162                for (i = 0; (c = charset[i]) != 0; i++)
 163                        charset[i] = tolower(c);
 164        }
 165        return 0;
 166}
 167
 168static int handle_content_type(char *line)
 169{
 170        *multipart_boundary = 0;
 171        if (slurp_attr(line, "boundary=", multipart_boundary + 2)) {
 172                memcpy(multipart_boundary, "--", 2);
 173                multipart_boundary_len = strlen(multipart_boundary);
 174        }
 175        slurp_attr(line, "charset=", charset);
 176        return 0;
 177}
 178
 179static int handle_content_transfer_encoding(char *line)
 180{
 181        if (strcasestr(line, "base64"))
 182                transfer_encoding = TE_BASE64;
 183        else if (strcasestr(line, "quoted-printable"))
 184                transfer_encoding = TE_QP;
 185        else
 186                transfer_encoding = TE_DONTCARE;
 187        return 0;
 188}
 189
 190static int is_multipart_boundary(const char *line)
 191{
 192        return (!memcmp(line, multipart_boundary, multipart_boundary_len));
 193}
 194
 195static int eatspace(char *line)
 196{
 197        int len = strlen(line);
 198        while (len > 0 && isspace(line[len-1]))
 199                line[--len] = 0;
 200        return len;
 201}
 202
 203#define SEEN_FROM 01
 204#define SEEN_DATE 02
 205#define SEEN_SUBJECT 04
 206
 207/* First lines of body can have From:, Date:, and Subject: */
 208static int handle_inbody_header(int *seen, char *line)
 209{
 210        if (!memcmp("From:", line, 5) && isspace(line[5])) {
 211                if (!(*seen & SEEN_FROM) && handle_from(line+6)) {
 212                        *seen |= SEEN_FROM;
 213                        return 1;
 214                }
 215        }
 216        if (!memcmp("Date:", line, 5) && isspace(line[5])) {
 217                if (!(*seen & SEEN_DATE)) {
 218                        handle_date(line+6);
 219                        *seen |= SEEN_DATE;
 220                        return 1;
 221                }
 222        }
 223        if (!memcmp("Subject:", line, 8) && isspace(line[8])) {
 224                if (!(*seen & SEEN_SUBJECT)) {
 225                        handle_subject(line+9);
 226                        *seen |= SEEN_SUBJECT;
 227                        return 1;
 228                }
 229        }
 230        if (!memcmp("[PATCH]", line, 7) && isspace(line[7])) {
 231                if (!(*seen & SEEN_SUBJECT)) {
 232                        handle_subject(line);
 233                        *seen |= SEEN_SUBJECT;
 234                        return 1;
 235                }
 236        }
 237        return 0;
 238}
 239
 240static char *cleanup_subject(char *subject)
 241{
 242        if (keep_subject)
 243                return subject;
 244        for (;;) {
 245                char *p;
 246                int len, remove;
 247                switch (*subject) {
 248                case 'r': case 'R':
 249                        if (!memcmp("e:", subject+1, 2)) {
 250                                subject +=3;
 251                                continue;
 252                        }
 253                        break;
 254                case ' ': case '\t': case ':':
 255                        subject++;
 256                        continue;
 257
 258                case '[':
 259                        p = strchr(subject, ']');
 260                        if (!p) {
 261                                subject++;
 262                                continue;
 263                        }
 264                        len = strlen(p);
 265                        remove = p - subject;
 266                        if (remove <= len *2) {
 267                                subject = p+1;
 268                                continue;
 269                        }       
 270                        break;
 271                }
 272                return subject;
 273        }
 274}                       
 275
 276static void cleanup_space(char *buf)
 277{
 278        unsigned char c;
 279        while ((c = *buf) != 0) {
 280                buf++;
 281                if (isspace(c)) {
 282                        buf[-1] = ' ';
 283                        c = *buf;
 284                        while (isspace(c)) {
 285                                int len = strlen(buf);
 286                                memmove(buf, buf+1, len);
 287                                c = *buf;
 288                        }
 289                }
 290        }
 291}
 292
 293typedef int (*header_fn_t)(char *);
 294struct header_def {
 295        const char *name;
 296        header_fn_t func;
 297        int namelen;
 298};
 299
 300static void check_header(char *line, int len, struct header_def *header)
 301{
 302        int i;
 303
 304        if (header[0].namelen <= 0) {
 305                for (i = 0; header[i].name; i++)
 306                        header[i].namelen = strlen(header[i].name);
 307        }
 308        for (i = 0; header[i].name; i++) {
 309                int len = header[i].namelen;
 310                if (!strncasecmp(line, header[i].name, len) &&
 311                    line[len] == ':' && isspace(line[len + 1])) {
 312                        header[i].func(line + len + 2);
 313                        break;
 314                }
 315        }
 316}
 317
 318static void check_subheader_line(char *line, int len)
 319{
 320        static struct header_def header[] = {
 321                { "Content-Type", handle_subcontent_type },
 322                { "Content-Transfer-Encoding",
 323                  handle_content_transfer_encoding },
 324                { NULL },
 325        };
 326        check_header(line, len, header);
 327}
 328static void check_header_line(char *line, int len)
 329{
 330        static struct header_def header[] = {
 331                { "From", handle_from },
 332                { "Date", handle_date },
 333                { "Subject", handle_subject },
 334                { "Content-Type", handle_content_type },
 335                { "Content-Transfer-Encoding",
 336                  handle_content_transfer_encoding },
 337                { NULL },
 338        };
 339        check_header(line, len, header);
 340}
 341
 342static int read_one_header_line(char *line, int sz, FILE *in)
 343{
 344        int ofs = 0;
 345        while (ofs < sz) {
 346                int peek, len;
 347                if (fgets(line + ofs, sz - ofs, in) == NULL)
 348                        return ofs;
 349                len = eatspace(line + ofs);
 350                if (len == 0)
 351                        return ofs;
 352                peek = fgetc(in); ungetc(peek, in);
 353                if (peek == ' ' || peek == '\t') {
 354                        /* Yuck, 2822 header "folding" */
 355                        ofs += len;
 356                        continue;
 357                }
 358                return ofs + len;
 359        }
 360        return ofs;
 361}
 362
 363static unsigned hexval(int c)
 364{
 365        if (c >= '0' && c <= '9')
 366                return c - '0';
 367        if (c >= 'a' && c <= 'f')
 368                return c - 'a' + 10;
 369        if (c >= 'A' && c <= 'F')
 370                return c - 'A' + 10;
 371        return ~0;
 372}
 373
 374static int decode_q_segment(char *in, char *ot, char *ep)
 375{
 376        int c;
 377        while ((c = *in++) != 0 && (in <= ep)) {
 378                if (c == '=') {
 379                        int d = *in++;
 380                        if (d == '\n' || !d)
 381                                break; /* drop trailing newline */
 382                        *ot++ = ((hexval(d) << 4) | hexval(*in++));
 383                }
 384                else
 385                        *ot++ = c;
 386        }
 387        *ot = 0;
 388        return 0;
 389}
 390
 391static int decode_b_segment(char *in, char *ot, char *ep)
 392{
 393        /* Decode in..ep, possibly in-place to ot */
 394        int c, pos = 0, acc = 0;
 395
 396        while ((c = *in++) != 0 && (in <= ep)) {
 397                if (c == '+')
 398                        c = 62;
 399                else if (c == '/')
 400                        c = 63;
 401                else if ('A' <= c && c <= 'Z')
 402                        c -= 'A';
 403                else if ('a' <= c && c <= 'z')
 404                        c -= 'a' - 26;
 405                else if ('0' <= c && c <= '9')
 406                        c -= '0' - 52;
 407                else if (c == '=') {
 408                        /* padding is almost like (c == 0), except we do
 409                         * not output NUL resulting only from it;
 410                         * for now we just trust the data.
 411                         */
 412                        c = 0;
 413                }
 414                else
 415                        continue; /* garbage */
 416                switch (pos++) {
 417                case 0:
 418                        acc = (c << 2);
 419                        break;
 420                case 1:
 421                        *ot++ = (acc | (c >> 4));
 422                        acc = (c & 15) << 4;
 423                        break;
 424                case 2:
 425                        *ot++ = (acc | (c >> 2));
 426                        acc = (c & 3) << 6;
 427                        break;
 428                case 3:
 429                        *ot++ = (acc | c);
 430                        acc = pos = 0;
 431                        break;
 432                }
 433        }
 434        *ot = 0;
 435        return 0;
 436}
 437
 438static void convert_to_utf8(char *line, char *charset)
 439{
 440        if (*charset) {
 441                char *in, *out;
 442                size_t insize, outsize, nrc;
 443                char outbuf[4096]; /* cheat */
 444                iconv_t conv = iconv_open("utf-8", charset);
 445
 446                if (conv == (iconv_t) -1) {
 447                        fprintf(stderr, "cannot convert from %s to utf-8\n",
 448                                charset);
 449                        *charset = 0;
 450                        return;
 451                }
 452                in = line;
 453                insize = strlen(in);
 454                out = outbuf;
 455                outsize = sizeof(outbuf);
 456                nrc = iconv(conv, &in, &insize, &out, &outsize);
 457                iconv_close(conv);
 458                if (nrc == (size_t) -1)
 459                        return;
 460                *out = 0;
 461                strcpy(line, outbuf);
 462        }
 463}
 464
 465static void decode_header_bq(char *it)
 466{
 467        char *in, *out, *ep, *cp, *sp;
 468        char outbuf[1000];
 469
 470        in = it;
 471        out = outbuf;
 472        while ((ep = strstr(in, "=?")) != NULL) {
 473                int sz, encoding;
 474                char charset_q[256], piecebuf[256];
 475                if (in != ep) {
 476                        sz = ep - in;
 477                        memcpy(out, in, sz);
 478                        out += sz;
 479                        in += sz;
 480                }
 481                /* E.g.
 482                 * ep : "=?iso-2022-jp?B?GyR...?= foo"
 483                 * ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz"
 484                 */
 485                ep += 2;
 486                cp = strchr(ep, '?');
 487                if (!cp)
 488                        return; /* no munging */
 489                for (sp = ep; sp < cp; sp++)
 490                        charset_q[sp - ep] = tolower(*sp);
 491                charset_q[cp - ep] = 0;
 492                encoding = cp[1];
 493                if (!encoding || cp[2] != '?')
 494                        return; /* no munging */
 495                ep = strstr(cp + 3, "?=");
 496                if (!ep)
 497                        return; /* no munging */
 498                switch (tolower(encoding)) {
 499                default:
 500                        return; /* no munging */
 501                case 'b':
 502                        sz = decode_b_segment(cp + 3, piecebuf, ep);
 503                        break;
 504                case 'q':
 505                        sz = decode_q_segment(cp + 3, piecebuf, ep);
 506                        break;
 507                }
 508                if (sz < 0)
 509                        return;
 510                if (metainfo_utf8)
 511                        convert_to_utf8(piecebuf, charset_q);
 512                strcpy(out, piecebuf);
 513                out += strlen(out);
 514                in = ep + 2;
 515        }
 516        strcpy(out, in);
 517        strcpy(it, outbuf);
 518}
 519
 520static void decode_transfer_encoding(char *line)
 521{
 522        char *ep;
 523
 524        switch (transfer_encoding) {
 525        case TE_QP:
 526                ep = line + strlen(line);
 527                decode_q_segment(line, line, ep);
 528                break;
 529        case TE_BASE64:
 530                ep = line + strlen(line);
 531                decode_b_segment(line, line, ep);
 532                break;
 533        case TE_DONTCARE:
 534                break;
 535        }
 536}
 537
 538static void handle_info(void)
 539{
 540        char *sub;
 541        static int done_info = 0;
 542
 543        if (done_info)
 544                return;
 545
 546        done_info = 1;
 547        sub = cleanup_subject(subject);
 548        cleanup_space(name);
 549        cleanup_space(date);
 550        cleanup_space(email);
 551        cleanup_space(sub);
 552
 553        /* Unwrap inline B and Q encoding, and optionally
 554         * normalize the meta information to utf8.
 555         */
 556        decode_header_bq(name);
 557        decode_header_bq(date);
 558        decode_header_bq(email);
 559        decode_header_bq(sub);
 560        printf("Author: %s\nEmail: %s\nSubject: %s\nDate: %s\n\n",
 561               name, email, sub, date);
 562}
 563
 564/* We are inside message body and have read line[] already.
 565 * Spit out the commit log.
 566 */
 567static int handle_commit_msg(void)
 568{
 569        if (!cmitmsg)
 570                return 0;
 571        do {
 572                if (!memcmp("diff -", line, 6) ||
 573                    !memcmp("---", line, 3) ||
 574                    !memcmp("Index: ", line, 7))
 575                        break;
 576                if ((multipart_boundary[0] && is_multipart_boundary(line))) {
 577                        /* We come here when the first part had only
 578                         * the commit message without any patch.  We
 579                         * pretend we have not seen this line yet, and
 580                         * go back to the loop.
 581                         */
 582                        return 1;
 583                }
 584
 585                /* Unwrap transfer encoding and optionally
 586                 * normalize the log message to UTF-8.
 587                 */
 588                decode_transfer_encoding(line);
 589                if (metainfo_utf8)
 590                        convert_to_utf8(line, charset);
 591                fputs(line, cmitmsg);
 592        } while (fgets(line, sizeof(line), stdin) != NULL);
 593        fclose(cmitmsg);
 594        cmitmsg = NULL;
 595        return 0;
 596}
 597
 598/* We have done the commit message and have the first
 599 * line of the patch in line[].
 600 */
 601static void handle_patch(void)
 602{
 603        do {
 604                if (multipart_boundary[0] && is_multipart_boundary(line))
 605                        break;
 606                /* Only unwrap transfer encoding but otherwise do not
 607                 * do anything.  We do *NOT* want UTF-8 conversion
 608                 * here; we are dealing with the user payload.
 609                 */
 610                decode_transfer_encoding(line);
 611                fputs(line, patchfile);
 612                patch_lines++;
 613        } while (fgets(line, sizeof(line), stdin) != NULL);
 614}
 615
 616/* multipart boundary and transfer encoding are set up for us, and we
 617 * are at the end of the sub header.  do equivalent of handle_body up
 618 * to the next boundary without closing patchfile --- we will expect
 619 * that the first part to contain commit message and a patch, and
 620 * handle other parts as pure patches.
 621 */
 622static int handle_multipart_one_part(void)
 623{
 624        int seen = 0;
 625        int n = 0;
 626        int len;
 627
 628        while (fgets(line, sizeof(line), stdin) != NULL) {
 629        again:
 630                len = eatspace(line);
 631                n++;
 632                if (!len)
 633                        continue;
 634                if (is_multipart_boundary(line))
 635                        break;
 636                if (0 <= seen && handle_inbody_header(&seen, line))
 637                        continue;
 638                seen = -1; /* no more inbody headers */
 639                line[len] = '\n';
 640                handle_info();
 641                if (handle_commit_msg())
 642                        goto again;
 643                handle_patch();
 644                break;
 645        }
 646        if (n == 0)
 647                return -1;
 648        return 0;
 649}
 650
 651static void handle_multipart_body(void)
 652{
 653        int part_num = 0;
 654
 655        /* Skip up to the first boundary */
 656        while (fgets(line, sizeof(line), stdin) != NULL)
 657                if (is_multipart_boundary(line)) {
 658                        part_num = 1;
 659                        break;
 660                }
 661        if (!part_num)
 662                return;
 663        /* We are on boundary line.  Start slurping the subhead. */
 664        while (1) {
 665                int len = read_one_header_line(line, sizeof(line), stdin);
 666                if (!len) {
 667                        if (handle_multipart_one_part() < 0)
 668                                return;
 669                }
 670                else
 671                        check_subheader_line(line, len);
 672        }
 673        fclose(patchfile);
 674        if (!patch_lines) {
 675                fprintf(stderr, "No patch found\n");
 676                exit(1);
 677        }
 678}
 679
 680/* Non multipart message */
 681static void handle_body(void)
 682{
 683        int seen = 0;
 684
 685        while (fgets(line, sizeof(line), stdin) != NULL) {
 686                int len = eatspace(line);
 687                if (!len)
 688                        continue;
 689                if (0 <= seen && handle_inbody_header(&seen, line))
 690                        continue;
 691                seen = -1; /* no more inbody headers */
 692                line[len] = '\n';
 693                handle_info();
 694                handle_commit_msg();
 695                handle_patch();
 696                break;
 697        }
 698        fclose(patchfile);
 699        if (!patch_lines) {
 700                fprintf(stderr, "No patch found\n");
 701                exit(1);
 702        }
 703}
 704
 705static const char mailinfo_usage[] =
 706        "git-mailinfo [-k] [-u] msg patch <mail >info";
 707
 708static void usage(void) {
 709        fprintf(stderr, "%s\n", mailinfo_usage);
 710        exit(1);
 711}
 712
 713int main(int argc, char **argv)
 714{
 715        while (1 < argc && argv[1][0] == '-') {
 716                if (!strcmp(argv[1], "-k"))
 717                        keep_subject = 1;
 718                else if (!strcmp(argv[1], "-u"))
 719                        metainfo_utf8 = 1;
 720                else
 721                        usage();
 722                argc--; argv++;
 723        }
 724
 725        if (argc != 3)
 726                usage();
 727        cmitmsg = fopen(argv[1], "w");
 728        if (!cmitmsg) {
 729                perror(argv[1]);
 730                exit(1);
 731        }
 732        patchfile = fopen(argv[2], "w");
 733        if (!patchfile) {
 734                perror(argv[2]);
 735                exit(1);
 736        }
 737        while (1) {
 738                int len = read_one_header_line(line, sizeof(line), stdin);
 739                if (!len) {
 740                        if (multipart_boundary[0])
 741                                handle_multipart_body();
 742                        else
 743                                handle_body();
 744                        break;
 745                }
 746                check_header_line(line, len);
 747        }
 748        return 0;
 749}