Andrew's git / gitweb.git / t/t4256/1/mailinfo.c.orig
?
t / t4256 / 1 / mailinfo.c.origon commit i18n: make GETTEXT_POISON a runtime option (6cdccfc)
   1#include "cache.h"
   2#include "config.h"
   3#include "utf8.h"
   4#include "strbuf.h"
   5#include "mailinfo.h"
   6
   7static void cleanup_space(struct strbuf *sb)
   8{
   9        size_t pos, cnt;
  10        for (pos = 0; pos < sb->len; pos++) {
  11                if (isspace(sb->buf[pos])) {
  12                        sb->buf[pos] = ' ';
  13                        for (cnt = 0; isspace(sb->buf[pos + cnt + 1]); cnt++);
  14                        strbuf_remove(sb, pos + 1, cnt);
  15                }
  16        }
  17}
  18
  19static void get_sane_name(struct strbuf *out, struct strbuf *name, struct strbuf *email)
  20{
  21        struct strbuf *src = name;
  22        if (name->len < 3 || 60 < name->len || strchr(name->buf, '@') ||
  23                strchr(name->buf, '<') || strchr(name->buf, '>'))
  24                src = email;
  25        else if (name == out)
  26                return;
  27        strbuf_reset(out);
  28        strbuf_addbuf(out, src);
  29}
  30
  31static void parse_bogus_from(struct mailinfo *mi, const struct strbuf *line)
  32{
  33        /* John Doe <johndoe> */
  34
  35        char *bra, *ket;
  36        /* This is fallback, so do not bother if we already have an
  37         * e-mail address.
  38         */
  39        if (mi->email.len)
  40                return;
  41
  42        bra = strchr(line->buf, '<');
  43        if (!bra)
  44                return;
  45        ket = strchr(bra, '>');
  46        if (!ket)
  47                return;
  48
  49        strbuf_reset(&mi->email);
  50        strbuf_add(&mi->email, bra + 1, ket - bra - 1);
  51
  52        strbuf_reset(&mi->name);
  53        strbuf_add(&mi->name, line->buf, bra - line->buf);
  54        strbuf_trim(&mi->name);
  55        get_sane_name(&mi->name, &mi->name, &mi->email);
  56}
  57
  58static const char *unquote_comment(struct strbuf *outbuf, const char *in)
  59{
  60        int c;
  61        int take_next_literally = 0;
  62
  63        strbuf_addch(outbuf, '(');
  64
  65        while ((c = *in++) != 0) {
  66                if (take_next_literally == 1) {
  67                        take_next_literally = 0;
  68                } else {
  69                        switch (c) {
  70                        case '\\':
  71                                take_next_literally = 1;
  72                                continue;
  73                        case '(':
  74                                in = unquote_comment(outbuf, in);
  75                                continue;
  76                        case ')':
  77                                strbuf_addch(outbuf, ')');
  78                                return in;
  79                        }
  80                }
  81
  82                strbuf_addch(outbuf, c);
  83        }
  84
  85        return in;
  86}
  87
  88static const char *unquote_quoted_string(struct strbuf *outbuf, const char *in)
  89{
  90        int c;
  91        int take_next_literally = 0;
  92
  93        while ((c = *in++) != 0) {
  94                if (take_next_literally == 1) {
  95                        take_next_literally = 0;
  96                } else {
  97                        switch (c) {
  98                        case '\\':
  99                                take_next_literally = 1;
 100                                continue;
 101                        case '"':
 102                                return in;
 103                        }
 104                }
 105
 106                strbuf_addch(outbuf, c);
 107        }
 108
 109        return in;
 110}
 111
 112static void unquote_quoted_pair(struct strbuf *line)
 113{
 114        struct strbuf outbuf;
 115        const char *in = line->buf;
 116        int c;
 117
 118        strbuf_init(&outbuf, line->len);
 119
 120        while ((c = *in++) != 0) {
 121                switch (c) {
 122                case '"':
 123                        in = unquote_quoted_string(&outbuf, in);
 124                        continue;
 125                case '(':
 126                        in = unquote_comment(&outbuf, in);
 127                        continue;
 128                }
 129
 130                strbuf_addch(&outbuf, c);
 131        }
 132
 133        strbuf_swap(&outbuf, line);
 134        strbuf_release(&outbuf);
 135
 136}
 137
 138static void handle_from(struct mailinfo *mi, const struct strbuf *from)
 139{
 140        char *at;
 141        size_t el;
 142        struct strbuf f;
 143
 144        strbuf_init(&f, from->len);
 145        strbuf_addbuf(&f, from);
 146
 147        unquote_quoted_pair(&f);
 148
 149        at = strchr(f.buf, '@');
 150        if (!at) {
 151                parse_bogus_from(mi, from);
 152                goto out;
 153        }
 154
 155        /*
 156         * If we already have one email, don't take any confusing lines
 157         */
 158        if (mi->email.len && strchr(at + 1, '@'))
 159                goto out;
 160
 161        /* Pick up the string around '@', possibly delimited with <>
 162         * pair; that is the email part.
 163         */
 164        while (at > f.buf) {
 165                char c = at[-1];
 166                if (isspace(c))
 167                        break;
 168                if (c == '<') {
 169                        at[-1] = ' ';
 170                        break;
 171                }
 172                at--;
 173        }
 174        el = strcspn(at, " \n\t\r\v\f>");
 175        strbuf_reset(&mi->email);
 176        strbuf_add(&mi->email, at, el);
 177        strbuf_remove(&f, at - f.buf, el + (at[el] ? 1 : 0));
 178
 179        /* The remainder is name.  It could be
 180         *
 181         * - "John Doe <john.doe@xz>"                   (a), or
 182         * - "john.doe@xz (John Doe)"                   (b), or
 183         * - "John (zzz) Doe <john.doe@xz> (Comment)"   (c)
 184         *
 185         * but we have removed the email part, so
 186         *
 187         * - remove extra spaces which could stay after email (case 'c'), and
 188         * - trim from both ends, possibly removing the () pair at the end
 189         *   (cases 'a' and 'b').
 190         */
 191        cleanup_space(&f);
 192        strbuf_trim(&f);
 193        if (f.buf[0] == '(' && f.len && f.buf[f.len - 1] == ')') {
 194                strbuf_remove(&f, 0, 1);
 195                strbuf_setlen(&f, f.len - 1);
 196        }
 197
 198        get_sane_name(&mi->name, &f, &mi->email);
 199out:
 200        strbuf_release(&f);
 201}
 202
 203static void handle_header(struct strbuf **out, const struct strbuf *line)
 204{
 205        if (!*out) {
 206                *out = xmalloc(sizeof(struct strbuf));
 207                strbuf_init(*out, line->len);
 208        } else
 209                strbuf_reset(*out);
 210
 211        strbuf_addbuf(*out, line);
 212}
 213
 214/* NOTE NOTE NOTE.  We do not claim we do full MIME.  We just attempt
 215 * to have enough heuristics to grok MIME encoded patches often found
 216 * on our mailing lists.  For example, we do not even treat header lines
 217 * case insensitively.
 218 */
 219
 220static int slurp_attr(const char *line, const char *name, struct strbuf *attr)
 221{
 222        const char *ends, *ap = strcasestr(line, name);
 223        size_t sz;
 224
 225        strbuf_setlen(attr, 0);
 226        if (!ap)
 227                return 0;
 228        ap += strlen(name);
 229        if (*ap == '"') {
 230                ap++;
 231                ends = "\"";
 232        }
 233        else
 234                ends = "; \t";
 235        sz = strcspn(ap, ends);
 236        strbuf_add(attr, ap, sz);
 237        return 1;
 238}
 239
 240static void handle_content_type(struct mailinfo *mi, struct strbuf *line)
 241{
 242        struct strbuf *boundary = xmalloc(sizeof(struct strbuf));
 243        strbuf_init(boundary, line->len);
 244
 245        if (slurp_attr(line->buf, "boundary=", boundary)) {
 246                strbuf_insert(boundary, 0, "--", 2);
 247                if (++mi->content_top >= &mi->content[MAX_BOUNDARIES]) {
 248                        error("Too many boundaries to handle");
 249                        mi->input_error = -1;
 250                        mi->content_top = &mi->content[MAX_BOUNDARIES] - 1;
 251                        return;
 252                }
 253                *(mi->content_top) = boundary;
 254                boundary = NULL;
 255        }
 256        slurp_attr(line->buf, "charset=", &mi->charset);
 257
 258        if (boundary) {
 259                strbuf_release(boundary);
 260                free(boundary);
 261        }
 262}
 263
 264static void handle_content_transfer_encoding(struct mailinfo *mi,
 265                                             const struct strbuf *line)
 266{
 267        if (strcasestr(line->buf, "base64"))
 268                mi->transfer_encoding = TE_BASE64;
 269        else if (strcasestr(line->buf, "quoted-printable"))
 270                mi->transfer_encoding = TE_QP;
 271        else
 272                mi->transfer_encoding = TE_DONTCARE;
 273}
 274
 275static int is_multipart_boundary(struct mailinfo *mi, const struct strbuf *line)
 276{
 277        struct strbuf *content_top = *(mi->content_top);
 278
 279        return ((content_top->len <= line->len) &&
 280                !memcmp(line->buf, content_top->buf, content_top->len));
 281}
 282
 283static void cleanup_subject(struct mailinfo *mi, struct strbuf *subject)
 284{
 285        size_t at = 0;
 286
 287        while (at < subject->len) {
 288                char *pos;
 289                size_t remove;
 290
 291                switch (subject->buf[at]) {
 292                case 'r': case 'R':
 293                        if (subject->len <= at + 3)
 294                                break;
 295                        if ((subject->buf[at + 1] == 'e' ||
 296                             subject->buf[at + 1] == 'E') &&
 297                            subject->buf[at + 2] == ':') {
 298                                strbuf_remove(subject, at, 3);
 299                                continue;
 300                        }
 301                        at++;
 302                        break;
 303                case ' ': case '\t': case ':':
 304                        strbuf_remove(subject, at, 1);
 305                        continue;
 306                case '[':
 307                        pos = strchr(subject->buf + at, ']');
 308                        if (!pos)
 309                                break;
 310                        remove = pos - subject->buf + at + 1;
 311                        if (!mi->keep_non_patch_brackets_in_subject ||
 312                            (7 <= remove &&
 313                             memmem(subject->buf + at, remove, "PATCH", 5)))
 314                                strbuf_remove(subject, at, remove);
 315                        else {
 316                                at += remove;
 317                                /*
 318                                 * If the input had a space after the ], keep
 319                                 * it.  We don't bother with finding the end of
 320                                 * the space, since we later normalize it
 321                                 * anyway.
 322                                 */
 323                                if (isspace(subject->buf[at]))
 324                                        at += 1;
 325                        }
 326                        continue;
 327                }
 328                break;
 329        }
 330        strbuf_trim(subject);
 331}
 332
 333#define MAX_HDR_PARSED 10
 334static const char *header[MAX_HDR_PARSED] = {
 335        "From","Subject","Date",
 336};
 337
 338static inline int cmp_header(const struct strbuf *line, const char *hdr)
 339{
 340        int len = strlen(hdr);
 341        return !strncasecmp(line->buf, hdr, len) && line->len > len &&
 342                        line->buf[len] == ':' && isspace(line->buf[len + 1]);
 343}
 344
 345static int is_format_patch_separator(const char *line, int len)
 346{
 347        static const char SAMPLE[] =
 348                "From e6807f3efca28b30decfecb1732a56c7db1137ee Mon Sep 17 00:00:00 2001\n";
 349        const char *cp;
 350
 351        if (len != strlen(SAMPLE))
 352                return 0;
 353        if (!skip_prefix(line, "From ", &cp))
 354                return 0;
 355        if (strspn(cp, "0123456789abcdef") != 40)
 356                return 0;
 357        cp += 40;
 358        return !memcmp(SAMPLE + (cp - line), cp, strlen(SAMPLE) - (cp - line));
 359}
 360
 361static struct strbuf *decode_q_segment(const struct strbuf *q_seg, int rfc2047)
 362{
 363        const char *in = q_seg->buf;
 364        int c;
 365        struct strbuf *out = xmalloc(sizeof(struct strbuf));
 366        strbuf_init(out, q_seg->len);
 367
 368        while ((c = *in++) != 0) {
 369                if (c == '=') {
 370                        int ch, d = *in;
 371                        if (d == '\n' || !d)
 372                                break; /* drop trailing newline */
 373                        ch = hex2chr(in);
 374                        if (ch >= 0) {
 375                                strbuf_addch(out, ch);
 376                                in += 2;
 377                                continue;
 378                        }
 379                        /* garbage -- fall through */
 380                }
 381                if (rfc2047 && c == '_') /* rfc2047 4.2 (2) */
 382                        c = 0x20;
 383                strbuf_addch(out, c);
 384        }
 385        return out;
 386}
 387
 388static struct strbuf *decode_b_segment(const struct strbuf *b_seg)
 389{
 390        /* Decode in..ep, possibly in-place to ot */
 391        int c, pos = 0, acc = 0;
 392        const char *in = b_seg->buf;
 393        struct strbuf *out = xmalloc(sizeof(struct strbuf));
 394        strbuf_init(out, b_seg->len);
 395
 396        while ((c = *in++) != 0) {
 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
 408                        continue; /* garbage */
 409                switch (pos++) {
 410                case 0:
 411                        acc = (c << 2);
 412                        break;
 413                case 1:
 414                        strbuf_addch(out, (acc | (c >> 4)));
 415                        acc = (c & 15) << 4;
 416                        break;
 417                case 2:
 418                        strbuf_addch(out, (acc | (c >> 2)));
 419                        acc = (c & 3) << 6;
 420                        break;
 421                case 3:
 422                        strbuf_addch(out, (acc | c));
 423                        acc = pos = 0;
 424                        break;
 425                }
 426        }
 427        return out;
 428}
 429
 430static int convert_to_utf8(struct mailinfo *mi,
 431                           struct strbuf *line, const char *charset)
 432{
 433        char *out;
 434
 435        if (!mi->metainfo_charset || !charset || !*charset)
 436                return 0;
 437
 438        if (same_encoding(mi->metainfo_charset, charset))
 439                return 0;
 440        out = reencode_string(line->buf, mi->metainfo_charset, charset);
 441        if (!out) {
 442                mi->input_error = -1;
 443                return error("cannot convert from %s to %s",
 444                             charset, mi->metainfo_charset);
 445        }
 446        strbuf_attach(line, out, strlen(out), strlen(out));
 447        return 0;
 448}
 449
 450static void decode_header(struct mailinfo *mi, struct strbuf *it)
 451{
 452        char *in, *ep, *cp;
 453        struct strbuf outbuf = STRBUF_INIT, *dec;
 454        struct strbuf charset_q = STRBUF_INIT, piecebuf = STRBUF_INIT;
 455        int found_error = 1; /* pessimism */
 456
 457        in = it->buf;
 458        while (in - it->buf <= it->len && (ep = strstr(in, "=?")) != NULL) {
 459                int encoding;
 460                strbuf_reset(&charset_q);
 461                strbuf_reset(&piecebuf);
 462
 463                if (in != ep) {
 464                        /*
 465                         * We are about to process an encoded-word
 466                         * that begins at ep, but there is something
 467                         * before the encoded word.
 468                         */
 469                        char *scan;
 470                        for (scan = in; scan < ep; scan++)
 471                                if (!isspace(*scan))
 472                                        break;
 473
 474                        if (scan != ep || in == it->buf) {
 475                                /*
 476                                 * We should not lose that "something",
 477                                 * unless we have just processed an
 478                                 * encoded-word, and there is only LWS
 479                                 * before the one we are about to process.
 480                                 */
 481                                strbuf_add(&outbuf, in, ep - in);
 482                        }
 483                }
 484                /* E.g.
 485                 * ep : "=?iso-2022-jp?B?GyR...?= foo"
 486                 * ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz"
 487                 */
 488                ep += 2;
 489
 490                if (ep - it->buf >= it->len || !(cp = strchr(ep, '?')))
 491                        goto release_return;
 492
 493                if (cp + 3 - it->buf > it->len)
 494                        goto release_return;
 495                strbuf_add(&charset_q, ep, cp - ep);
 496
 497                encoding = cp[1];
 498                if (!encoding || cp[2] != '?')
 499                        goto release_return;
 500                ep = strstr(cp + 3, "?=");
 501                if (!ep)
 502                        goto release_return;
 503                strbuf_add(&piecebuf, cp + 3, ep - cp - 3);
 504                switch (tolower(encoding)) {
 505                default:
 506                        goto release_return;
 507                case 'b':
 508                        dec = decode_b_segment(&piecebuf);
 509                        break;
 510                case 'q':
 511                        dec = decode_q_segment(&piecebuf, 1);
 512                        break;
 513                }
 514                if (convert_to_utf8(mi, dec, charset_q.buf))
 515                        goto release_return;
 516
 517                strbuf_addbuf(&outbuf, dec);
 518                strbuf_release(dec);
 519                free(dec);
 520                in = ep + 2;
 521        }
 522        strbuf_addstr(&outbuf, in);
 523        strbuf_reset(it);
 524        strbuf_addbuf(it, &outbuf);
 525        found_error = 0;
 526release_return:
 527        strbuf_release(&outbuf);
 528        strbuf_release(&charset_q);
 529        strbuf_release(&piecebuf);
 530
 531        if (found_error)
 532                mi->input_error = -1;
 533}
 534
 535static int check_header(struct mailinfo *mi,
 536                        const struct strbuf *line,
 537                        struct strbuf *hdr_data[], int overwrite)
 538{
 539        int i, ret = 0, len;
 540        struct strbuf sb = STRBUF_INIT;
 541
 542        /* search for the interesting parts */
 543        for (i = 0; header[i]; i++) {
 544                int len = strlen(header[i]);
 545                if ((!hdr_data[i] || overwrite) && cmp_header(line, header[i])) {
 546                        /* Unwrap inline B and Q encoding, and optionally
 547                         * normalize the meta information to utf8.
 548                         */
 549                        strbuf_add(&sb, line->buf + len + 2, line->len - len - 2);
 550                        decode_header(mi, &sb);
 551                        handle_header(&hdr_data[i], &sb);
 552                        ret = 1;
 553                        goto check_header_out;
 554                }
 555        }
 556
 557        /* Content stuff */
 558        if (cmp_header(line, "Content-Type")) {
 559                len = strlen("Content-Type: ");
 560                strbuf_add(&sb, line->buf + len, line->len - len);
 561                decode_header(mi, &sb);
 562                strbuf_insert(&sb, 0, "Content-Type: ", len);
 563                handle_content_type(mi, &sb);
 564                ret = 1;
 565                goto check_header_out;
 566        }
 567        if (cmp_header(line, "Content-Transfer-Encoding")) {
 568                len = strlen("Content-Transfer-Encoding: ");
 569                strbuf_add(&sb, line->buf + len, line->len - len);
 570                decode_header(mi, &sb);
 571                handle_content_transfer_encoding(mi, &sb);
 572                ret = 1;
 573                goto check_header_out;
 574        }
 575        if (cmp_header(line, "Message-Id")) {
 576                len = strlen("Message-Id: ");
 577                strbuf_add(&sb, line->buf + len, line->len - len);
 578                decode_header(mi, &sb);
 579                if (mi->add_message_id)
 580                        mi->message_id = strbuf_detach(&sb, NULL);
 581                ret = 1;
 582                goto check_header_out;
 583        }
 584
 585check_header_out:
 586        strbuf_release(&sb);
 587        return ret;
 588}
 589
 590/*
 591 * Returns 1 if the given line or any line beginning with the given line is an
 592 * in-body header (that is, check_header will succeed when passed
 593 * mi->s_hdr_data).
 594 */
 595static int is_inbody_header(const struct mailinfo *mi,
 596                            const struct strbuf *line)
 597{
 598        int i;
 599        for (i = 0; header[i]; i++)
 600                if (!mi->s_hdr_data[i] && cmp_header(line, header[i]))
 601                        return 1;
 602        return 0;
 603}
 604
 605static void decode_transfer_encoding(struct mailinfo *mi, struct strbuf *line)
 606{
 607        struct strbuf *ret;
 608
 609        switch (mi->transfer_encoding) {
 610        case TE_QP:
 611                ret = decode_q_segment(line, 0);
 612                break;
 613        case TE_BASE64:
 614                ret = decode_b_segment(line);
 615                break;
 616        case TE_DONTCARE:
 617        default:
 618                return;
 619        }
 620        strbuf_reset(line);
 621        strbuf_addbuf(line, ret);
 622        strbuf_release(ret);
 623        free(ret);
 624}
 625
 626static inline int patchbreak(const struct strbuf *line)
 627{
 628        size_t i;
 629
 630        /* Beginning of a "diff -" header? */
 631        if (starts_with(line->buf, "diff -"))
 632                return 1;
 633
 634        /* CVS "Index: " line? */
 635        if (starts_with(line->buf, "Index: "))
 636                return 1;
 637
 638        /*
 639         * "--- <filename>" starts patches without headers
 640         * "---<sp>*" is a manual separator
 641         */
 642        if (line->len < 4)
 643                return 0;
 644
 645        if (starts_with(line->buf, "---")) {
 646                /* space followed by a filename? */
 647                if (line->buf[3] == ' ' && !isspace(line->buf[4]))
 648                        return 1;
 649                /* Just whitespace? */
 650                for (i = 3; i < line->len; i++) {
 651                        unsigned char c = line->buf[i];
 652                        if (c == '\n')
 653                                return 1;
 654                        if (!isspace(c))
 655                                break;
 656                }
 657                return 0;
 658        }
 659        return 0;
 660}
 661
 662static int is_scissors_line(const char *line)
 663{
 664        const char *c;
 665        int scissors = 0, gap = 0;
 666        const char *first_nonblank = NULL, *last_nonblank = NULL;
 667        int visible, perforation = 0, in_perforation = 0;
 668
 669        for (c = line; *c; c++) {
 670                if (isspace(*c)) {
 671                        if (in_perforation) {
 672                                perforation++;
 673                                gap++;
 674                        }
 675                        continue;
 676                }
 677                last_nonblank = c;
 678                if (first_nonblank == NULL)
 679                        first_nonblank = c;
 680                if (*c == '-') {
 681                        in_perforation = 1;
 682                        perforation++;
 683                        continue;
 684                }
 685                if ((!memcmp(c, ">8", 2) || !memcmp(c, "8<", 2) ||
 686                     !memcmp(c, ">%", 2) || !memcmp(c, "%<", 2))) {
 687                        in_perforation = 1;
 688                        perforation += 2;
 689                        scissors += 2;
 690                        c++;
 691                        continue;
 692                }
 693                in_perforation = 0;
 694        }
 695
 696        /*
 697         * The mark must be at least 8 bytes long (e.g. "-- >8 --").
 698         * Even though there can be arbitrary cruft on the same line
 699         * (e.g. "cut here"), in order to avoid misidentification, the
 700         * perforation must occupy more than a third of the visible
 701         * width of the line, and dashes and scissors must occupy more
 702         * than half of the perforation.
 703         */
 704
 705        if (first_nonblank && last_nonblank)
 706                visible = last_nonblank - first_nonblank + 1;
 707        else
 708                visible = 0;
 709        return (scissors && 8 <= visible &&
 710                visible < perforation * 3 &&
 711                gap * 2 < perforation);
 712}
 713
 714static void flush_inbody_header_accum(struct mailinfo *mi)
 715{
 716        if (!mi->inbody_header_accum.len)
 717                return;
 718        if (!check_header(mi, &mi->inbody_header_accum, mi->s_hdr_data, 0))
 719                BUG("inbody_header_accum, if not empty, must always contain a valid in-body header");
 720        strbuf_reset(&mi->inbody_header_accum);
 721}
 722
 723static int check_inbody_header(struct mailinfo *mi, const struct strbuf *line)
 724{
 725        if (mi->inbody_header_accum.len &&
 726            (line->buf[0] == ' ' || line->buf[0] == '\t')) {
 727                if (mi->use_scissors && is_scissors_line(line->buf)) {
 728                        /*
 729                         * This is a scissors line; do not consider this line
 730                         * as a header continuation line.
 731                         */
 732                        flush_inbody_header_accum(mi);
 733                        return 0;
 734                }
 735                strbuf_strip_suffix(&mi->inbody_header_accum, "\n");
 736                strbuf_addbuf(&mi->inbody_header_accum, line);
 737                return 1;
 738        }
 739
 740        flush_inbody_header_accum(mi);
 741
 742        if (starts_with(line->buf, ">From") && isspace(line->buf[5]))
 743                return is_format_patch_separator(line->buf + 1, line->len - 1);
 744        if (starts_with(line->buf, "[PATCH]") && isspace(line->buf[7])) {
 745                int i;
 746                for (i = 0; header[i]; i++)
 747                        if (!strcmp("Subject", header[i])) {
 748                                handle_header(&mi->s_hdr_data[i], line);
 749                                return 1;
 750                        }
 751                return 0;
 752        }
 753        if (is_inbody_header(mi, line)) {
 754                strbuf_addbuf(&mi->inbody_header_accum, line);
 755                return 1;
 756        }
 757        return 0;
 758}
 759
 760static int handle_commit_msg(struct mailinfo *mi, struct strbuf *line)
 761{
 762        assert(!mi->filter_stage);
 763
 764        if (mi->header_stage) {
 765                if (!line->len || (line->len == 1 && line->buf[0] == '\n')) {
 766                        if (mi->inbody_header_accum.len) {
 767                                flush_inbody_header_accum(mi);
 768                                mi->header_stage = 0;
 769                        }
 770                        return 0;
 771                }
 772        }
 773
 774        if (mi->use_inbody_headers && mi->header_stage) {
 775                mi->header_stage = check_inbody_header(mi, line);
 776                if (mi->header_stage)
 777                        return 0;
 778        } else
 779                /* Only trim the first (blank) line of the commit message
 780                 * when ignoring in-body headers.
 781                 */
 782                mi->header_stage = 0;
 783
 784        /* normalize the log message to UTF-8. */
 785        if (convert_to_utf8(mi, line, mi->charset.buf))
 786                return 0; /* mi->input_error already set */
 787
 788        if (mi->use_scissors && is_scissors_line(line->buf)) {
 789                int i;
 790
 791                strbuf_setlen(&mi->log_message, 0);
 792                mi->header_stage = 1;
 793
 794                /*
 795                 * We may have already read "secondary headers"; purge
 796                 * them to give ourselves a clean restart.
 797                 */
 798                for (i = 0; header[i]; i++) {
 799                        if (mi->s_hdr_data[i])
 800                                strbuf_release(mi->s_hdr_data[i]);
 801                        mi->s_hdr_data[i] = NULL;
 802                }
 803                return 0;
 804        }
 805
 806        if (patchbreak(line)) {
 807                if (mi->message_id)
 808                        strbuf_addf(&mi->log_message,
 809                                    "Message-Id: %s\n", mi->message_id);
 810                return 1;
 811        }
 812
 813        strbuf_addbuf(&mi->log_message, line);
 814        return 0;
 815}
 816
 817static void handle_patch(struct mailinfo *mi, const struct strbuf *line)
 818{
 819        fwrite(line->buf, 1, line->len, mi->patchfile);
 820        mi->patch_lines++;
 821}
 822
 823static void handle_filter(struct mailinfo *mi, struct strbuf *line)
 824{
 825        switch (mi->filter_stage) {
 826        case 0:
 827                if (!handle_commit_msg(mi, line))
 828                        break;
 829                mi->filter_stage++;
 830                /* fallthrough */
 831        case 1:
 832                handle_patch(mi, line);
 833                break;
 834        }
 835}
 836
 837static int is_rfc2822_header(const struct strbuf *line)
 838{
 839        /*
 840         * The section that defines the loosest possible
 841         * field name is "3.6.8 Optional fields".
 842         *
 843         * optional-field = field-name ":" unstructured CRLF
 844         * field-name = 1*ftext
 845         * ftext = %d33-57 / %59-126
 846         */
 847        int ch;
 848        char *cp = line->buf;
 849
 850        /* Count mbox From headers as headers */
 851        if (starts_with(cp, "From ") || starts_with(cp, ">From "))
 852                return 1;
 853
 854        while ((ch = *cp++)) {
 855                if (ch == ':')
 856                        return 1;
 857                if ((33 <= ch && ch <= 57) ||
 858                    (59 <= ch && ch <= 126))
 859                        continue;
 860                break;
 861        }
 862        return 0;
 863}
 864
 865static int read_one_header_line(struct strbuf *line, FILE *in)
 866{
 867        struct strbuf continuation = STRBUF_INIT;
 868
 869        /* Get the first part of the line. */
 870        if (strbuf_getline_lf(line, in))
 871                return 0;
 872
 873        /*
 874         * Is it an empty line or not a valid rfc2822 header?
 875         * If so, stop here, and return false ("not a header")
 876         */
 877        strbuf_rtrim(line);
 878        if (!line->len || !is_rfc2822_header(line)) {
 879                /* Re-add the newline */
 880                strbuf_addch(line, '\n');
 881                return 0;
 882        }
 883
 884        /*
 885         * Now we need to eat all the continuation lines..
 886         * Yuck, 2822 header "folding"
 887         */
 888        for (;;) {
 889                int peek;
 890
 891                peek = fgetc(in);
 892                if (peek == EOF)
 893                        break;
 894                ungetc(peek, in);
 895                if (peek != ' ' && peek != '\t')
 896                        break;
 897                if (strbuf_getline_lf(&continuation, in))
 898                        break;
 899                continuation.buf[0] = ' ';
 900                strbuf_rtrim(&continuation);
 901                strbuf_addbuf(line, &continuation);
 902        }
 903        strbuf_release(&continuation);
 904
 905        return 1;
 906}
 907
 908static int find_boundary(struct mailinfo *mi, struct strbuf *line)
 909{
 910        while (!strbuf_getline_lf(line, mi->input)) {
 911                if (*(mi->content_top) && is_multipart_boundary(mi, line))
 912                        return 1;
 913        }
 914        return 0;
 915}
 916
 917static int handle_boundary(struct mailinfo *mi, struct strbuf *line)
 918{
 919        struct strbuf newline = STRBUF_INIT;
 920
 921        strbuf_addch(&newline, '\n');
 922again:
 923        if (line->len >= (*(mi->content_top))->len + 2 &&
 924            !memcmp(line->buf + (*(mi->content_top))->len, "--", 2)) {
 925                /* we hit an end boundary */
 926                /* pop the current boundary off the stack */
 927                strbuf_release(*(mi->content_top));
 928                FREE_AND_NULL(*(mi->content_top));
 929
 930                /* technically won't happen as is_multipart_boundary()
 931                   will fail first.  But just in case..
 932                 */
 933                if (--mi->content_top < mi->content) {
 934                        error("Detected mismatched boundaries, can't recover");
 935                        mi->input_error = -1;
 936                        mi->content_top = mi->content;
 937                        strbuf_release(&newline);
 938                        return 0;
 939                }
 940                handle_filter(mi, &newline);
 941                strbuf_release(&newline);
 942                if (mi->input_error)
 943                        return 0;
 944
 945                /* skip to the next boundary */
 946                if (!find_boundary(mi, line))
 947                        return 0;
 948                goto again;
 949        }
 950
 951        /* set some defaults */
 952        mi->transfer_encoding = TE_DONTCARE;
 953        strbuf_reset(&mi->charset);
 954
 955        /* slurp in this section's info */
 956        while (read_one_header_line(line, mi->input))
 957                check_header(mi, line, mi->p_hdr_data, 0);
 958
 959        strbuf_release(&newline);
 960        /* replenish line */
 961        if (strbuf_getline_lf(line, mi->input))
 962                return 0;
 963        strbuf_addch(line, '\n');
 964        return 1;
 965}
 966
 967static void handle_body(struct mailinfo *mi, struct strbuf *line)
 968{
 969        struct strbuf prev = STRBUF_INIT;
 970
 971        /* Skip up to the first boundary */
 972        if (*(mi->content_top)) {
 973                if (!find_boundary(mi, line))
 974                        goto handle_body_out;
 975        }
 976
 977        do {
 978                /* process any boundary lines */
 979                if (*(mi->content_top) && is_multipart_boundary(mi, line)) {
 980                        /* flush any leftover */
 981                        if (prev.len) {
 982                                handle_filter(mi, &prev);
 983                                strbuf_reset(&prev);
 984                        }
 985                        if (!handle_boundary(mi, line))
 986                                goto handle_body_out;
 987                }
 988
 989                /* Unwrap transfer encoding */
 990                decode_transfer_encoding(mi, line);
 991
 992                switch (mi->transfer_encoding) {
 993                case TE_BASE64:
 994                case TE_QP:
 995                {
 996                        struct strbuf **lines, **it, *sb;
 997
 998                        /* Prepend any previous partial lines */
 999                        strbuf_insert(line, 0, prev.buf, prev.len);
1000                        strbuf_reset(&prev);
1001
1002                        /*
1003                         * This is a decoded line that may contain
1004                         * multiple new lines.  Pass only one chunk
1005                         * at a time to handle_filter()
1006                         */
1007                        lines = strbuf_split(line, '\n');
1008                        for (it = lines; (sb = *it); it++) {
1009                                if (*(it + 1) == NULL) /* The last line */
1010                                        if (sb->buf[sb->len - 1] != '\n') {
1011                                                /* Partial line, save it for later. */
1012                                                strbuf_addbuf(&prev, sb);
1013                                                break;
1014                                        }
1015                                handle_filter(mi, sb);
1016                        }
1017                        /*
1018                         * The partial chunk is saved in "prev" and will be
1019                         * appended by the next iteration of read_line_with_nul().
1020                         */
1021                        strbuf_list_free(lines);
1022                        break;
1023                }
1024                default:
1025                        handle_filter(mi, line);
1026                }
1027
1028                if (mi->input_error)
1029                        break;
1030        } while (!strbuf_getwholeline(line, mi->input, '\n'));
1031
1032        flush_inbody_header_accum(mi);
1033
1034handle_body_out:
1035        strbuf_release(&prev);
1036}
1037
1038static void output_header_lines(FILE *fout, const char *hdr, const struct strbuf *data)
1039{
1040        const char *sp = data->buf;
1041        while (1) {
1042                char *ep = strchr(sp, '\n');
1043                int len;
1044                if (!ep)
1045                        len = strlen(sp);
1046                else
1047                        len = ep - sp;
1048                fprintf(fout, "%s: %.*s\n", hdr, len, sp);
1049                if (!ep)
1050                        break;
1051                sp = ep + 1;
1052        }
1053}
1054
1055static void handle_info(struct mailinfo *mi)
1056{
1057        struct strbuf *hdr;
1058        int i;
1059
1060        for (i = 0; header[i]; i++) {
1061                /* only print inbody headers if we output a patch file */
1062                if (mi->patch_lines && mi->s_hdr_data[i])
1063                        hdr = mi->s_hdr_data[i];
1064                else if (mi->p_hdr_data[i])
1065                        hdr = mi->p_hdr_data[i];
1066                else
1067                        continue;
1068
1069                if (!strcmp(header[i], "Subject")) {
1070                        if (!mi->keep_subject) {
1071                                cleanup_subject(mi, hdr);
1072                                cleanup_space(hdr);
1073                        }
1074                        output_header_lines(mi->output, "Subject", hdr);
1075                } else if (!strcmp(header[i], "From")) {
1076                        cleanup_space(hdr);
1077                        handle_from(mi, hdr);
1078                        fprintf(mi->output, "Author: %s\n", mi->name.buf);
1079                        fprintf(mi->output, "Email: %s\n", mi->email.buf);
1080                } else {
1081                        cleanup_space(hdr);
1082                        fprintf(mi->output, "%s: %s\n", header[i], hdr->buf);
1083                }
1084        }
1085        fprintf(mi->output, "\n");
1086}
1087
1088int mailinfo(struct mailinfo *mi, const char *msg, const char *patch)
1089{
1090        FILE *cmitmsg;
1091        int peek;
1092        struct strbuf line = STRBUF_INIT;
1093
1094        cmitmsg = fopen(msg, "w");
1095        if (!cmitmsg) {
1096                perror(msg);
1097                return -1;
1098        }
1099        mi->patchfile = fopen(patch, "w");
1100        if (!mi->patchfile) {
1101                perror(patch);
1102                fclose(cmitmsg);
1103                return -1;
1104        }
1105
1106        mi->p_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->p_hdr_data)));
1107        mi->s_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->s_hdr_data)));
1108
1109        do {
1110                peek = fgetc(mi->input);
1111                if (peek == EOF) {
1112                        fclose(cmitmsg);
1113                        return error("empty patch: '%s'", patch);
1114                }
1115        } while (isspace(peek));
1116        ungetc(peek, mi->input);
1117
1118        /* process the email header */
1119        while (read_one_header_line(&line, mi->input))
1120                check_header(mi, &line, mi->p_hdr_data, 1);
1121
1122        handle_body(mi, &line);
1123        fwrite(mi->log_message.buf, 1, mi->log_message.len, cmitmsg);
1124        fclose(cmitmsg);
1125        fclose(mi->patchfile);
1126
1127        handle_info(mi);
1128        strbuf_release(&line);
1129        return mi->input_error;
1130}
1131
1132static int git_mailinfo_config(const char *var, const char *value, void *mi_)
1133{
1134        struct mailinfo *mi = mi_;
1135
1136        if (!starts_with(var, "mailinfo."))
1137                return git_default_config(var, value, NULL);
1138        if (!strcmp(var, "mailinfo.scissors")) {
1139                mi->use_scissors = git_config_bool(var, value);
1140                return 0;
1141        }
1142        /* perhaps others here */
1143        return 0;
1144}
1145
1146void setup_mailinfo(struct mailinfo *mi)
1147{
1148        memset(mi, 0, sizeof(*mi));
1149        strbuf_init(&mi->name, 0);
1150        strbuf_init(&mi->email, 0);
1151        strbuf_init(&mi->charset, 0);
1152        strbuf_init(&mi->log_message, 0);
1153        strbuf_init(&mi->inbody_header_accum, 0);
1154        mi->header_stage = 1;
1155        mi->use_inbody_headers = 1;
1156        mi->content_top = mi->content;
1157        git_config(git_mailinfo_config, mi);
1158}
1159
1160void clear_mailinfo(struct mailinfo *mi)
1161{
1162        int i;
1163
1164        strbuf_release(&mi->name);
1165        strbuf_release(&mi->email);
1166        strbuf_release(&mi->charset);
1167        strbuf_release(&mi->inbody_header_accum);
1168        free(mi->message_id);
1169
1170        if (mi->p_hdr_data)
1171                for (i = 0; mi->p_hdr_data[i]; i++)
1172                        strbuf_release(mi->p_hdr_data[i]);
1173        free(mi->p_hdr_data);
1174        if (mi->s_hdr_data)
1175                for (i = 0; mi->s_hdr_data[i]; i++)
1176                        strbuf_release(mi->s_hdr_data[i]);
1177        free(mi->s_hdr_data);
1178
1179        while (mi->content < mi->content_top) {
1180                free(*(mi->content_top));
1181                mi->content_top--;
1182        }
1183
1184        strbuf_release(&mi->log_message);
1185}