t / t4256 / 1 / mailinfo.con commit Merge branch 'jc/no-grepping-for-strerror-in-tests' (4e09a7b)
   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 int has_attr_value(const char *line, const char *name, const char *value)
 241{
 242        struct strbuf sb = STRBUF_INIT;
 243        int rc = slurp_attr(line, name, &sb) && !strcasecmp(sb.buf, value);
 244        strbuf_release(&sb);
 245        return rc;
 246}
 247
 248static void handle_content_type(struct mailinfo *mi, struct strbuf *line)
 249{
 250        struct strbuf *boundary = xmalloc(sizeof(struct strbuf));
 251        strbuf_init(boundary, line->len);
 252
 253        mi->format_flowed = has_attr_value(line->buf, "format=", "flowed");
 254        mi->delsp = has_attr_value(line->buf, "delsp=", "yes");
 255
 256        if (slurp_attr(line->buf, "boundary=", boundary)) {
 257                strbuf_insert(boundary, 0, "--", 2);
 258                if (++mi->content_top >= &mi->content[MAX_BOUNDARIES]) {
 259                        error("Too many boundaries to handle");
 260                        mi->input_error = -1;
 261                        mi->content_top = &mi->content[MAX_BOUNDARIES] - 1;
 262                        return;
 263                }
 264                *(mi->content_top) = boundary;
 265                boundary = NULL;
 266        }
 267        slurp_attr(line->buf, "charset=", &mi->charset);
 268
 269        if (boundary) {
 270                strbuf_release(boundary);
 271                free(boundary);
 272        }
 273}
 274
 275static void handle_content_transfer_encoding(struct mailinfo *mi,
 276                                             const struct strbuf *line)
 277{
 278        if (strcasestr(line->buf, "base64"))
 279                mi->transfer_encoding = TE_BASE64;
 280        else if (strcasestr(line->buf, "quoted-printable"))
 281                mi->transfer_encoding = TE_QP;
 282        else
 283                mi->transfer_encoding = TE_DONTCARE;
 284}
 285
 286static int is_multipart_boundary(struct mailinfo *mi, const struct strbuf *line)
 287{
 288        struct strbuf *content_top = *(mi->content_top);
 289
 290        return ((content_top->len <= line->len) &&
 291                !memcmp(line->buf, content_top->buf, content_top->len));
 292}
 293
 294static void cleanup_subject(struct mailinfo *mi, struct strbuf *subject)
 295{
 296        size_t at = 0;
 297
 298        while (at < subject->len) {
 299                char *pos;
 300                size_t remove;
 301
 302                switch (subject->buf[at]) {
 303                case 'r': case 'R':
 304                        if (subject->len <= at + 3)
 305                                break;
 306                        if ((subject->buf[at + 1] == 'e' ||
 307                             subject->buf[at + 1] == 'E') &&
 308                            subject->buf[at + 2] == ':') {
 309                                strbuf_remove(subject, at, 3);
 310                                continue;
 311                        }
 312                        at++;
 313                        break;
 314                case ' ': case '\t': case ':':
 315                        strbuf_remove(subject, at, 1);
 316                        continue;
 317                case '[':
 318                        pos = strchr(subject->buf + at, ']');
 319                        if (!pos)
 320                                break;
 321                        remove = pos - subject->buf + at + 1;
 322                        if (!mi->keep_non_patch_brackets_in_subject ||
 323                            (7 <= remove &&
 324                             memmem(subject->buf + at, remove, "PATCH", 5)))
 325                                strbuf_remove(subject, at, remove);
 326                        else {
 327                                at += remove;
 328                                /*
 329                                 * If the input had a space after the ], keep
 330                                 * it.  We don't bother with finding the end of
 331                                 * the space, since we later normalize it
 332                                 * anyway.
 333                                 */
 334                                if (isspace(subject->buf[at]))
 335                                        at += 1;
 336                        }
 337                        continue;
 338                }
 339                break;
 340        }
 341        strbuf_trim(subject);
 342}
 343
 344#define MAX_HDR_PARSED 10
 345static const char *header[MAX_HDR_PARSED] = {
 346        "From","Subject","Date",
 347};
 348
 349static inline int cmp_header(const struct strbuf *line, const char *hdr)
 350{
 351        int len = strlen(hdr);
 352        return !strncasecmp(line->buf, hdr, len) && line->len > len &&
 353                        line->buf[len] == ':' && isspace(line->buf[len + 1]);
 354}
 355
 356static int is_format_patch_separator(const char *line, int len)
 357{
 358        static const char SAMPLE[] =
 359                "From e6807f3efca28b30decfecb1732a56c7db1137ee Mon Sep 17 00:00:00 2001\n";
 360        const char *cp;
 361
 362        if (len != strlen(SAMPLE))
 363                return 0;
 364        if (!skip_prefix(line, "From ", &cp))
 365                return 0;
 366        if (strspn(cp, "0123456789abcdef") != 40)
 367                return 0;
 368        cp += 40;
 369        return !memcmp(SAMPLE + (cp - line), cp, strlen(SAMPLE) - (cp - line));
 370}
 371
 372static struct strbuf *decode_q_segment(const struct strbuf *q_seg, int rfc2047)
 373{
 374        const char *in = q_seg->buf;
 375        int c;
 376        struct strbuf *out = xmalloc(sizeof(struct strbuf));
 377        strbuf_init(out, q_seg->len);
 378
 379        while ((c = *in++) != 0) {
 380                if (c == '=') {
 381                        int ch, d = *in;
 382                        if (d == '\n' || !d)
 383                                break; /* drop trailing newline */
 384                        ch = hex2chr(in);
 385                        if (ch >= 0) {
 386                                strbuf_addch(out, ch);
 387                                in += 2;
 388                                continue;
 389                        }
 390                        /* garbage -- fall through */
 391                }
 392                if (rfc2047 && c == '_') /* rfc2047 4.2 (2) */
 393                        c = 0x20;
 394                strbuf_addch(out, c);
 395        }
 396        return out;
 397}
 398
 399static struct strbuf *decode_b_segment(const struct strbuf *b_seg)
 400{
 401        /* Decode in..ep, possibly in-place to ot */
 402        int c, pos = 0, acc = 0;
 403        const char *in = b_seg->buf;
 404        struct strbuf *out = xmalloc(sizeof(struct strbuf));
 405        strbuf_init(out, b_seg->len);
 406
 407        while ((c = *in++) != 0) {
 408                if (c == '+')
 409                        c = 62;
 410                else if (c == '/')
 411                        c = 63;
 412                else if ('A' <= c && c <= 'Z')
 413                        c -= 'A';
 414                else if ('a' <= c && c <= 'z')
 415                        c -= 'a' - 26;
 416                else if ('0' <= c && c <= '9')
 417                        c -= '0' - 52;
 418                else
 419                        continue; /* garbage */
 420                switch (pos++) {
 421                case 0:
 422                        acc = (c << 2);
 423                        break;
 424                case 1:
 425                        strbuf_addch(out, (acc | (c >> 4)));
 426                        acc = (c & 15) << 4;
 427                        break;
 428                case 2:
 429                        strbuf_addch(out, (acc | (c >> 2)));
 430                        acc = (c & 3) << 6;
 431                        break;
 432                case 3:
 433                        strbuf_addch(out, (acc | c));
 434                        acc = pos = 0;
 435                        break;
 436                }
 437        }
 438        return out;
 439}
 440
 441static int convert_to_utf8(struct mailinfo *mi,
 442                           struct strbuf *line, const char *charset)
 443{
 444        char *out;
 445
 446        if (!mi->metainfo_charset || !charset || !*charset)
 447                return 0;
 448
 449        if (same_encoding(mi->metainfo_charset, charset))
 450                return 0;
 451        out = reencode_string(line->buf, mi->metainfo_charset, charset);
 452        if (!out) {
 453                mi->input_error = -1;
 454                return error("cannot convert from %s to %s",
 455                             charset, mi->metainfo_charset);
 456        }
 457        strbuf_attach(line, out, strlen(out), strlen(out));
 458        return 0;
 459}
 460
 461static void decode_header(struct mailinfo *mi, struct strbuf *it)
 462{
 463        char *in, *ep, *cp;
 464        struct strbuf outbuf = STRBUF_INIT, *dec;
 465        struct strbuf charset_q = STRBUF_INIT, piecebuf = STRBUF_INIT;
 466        int found_error = 1; /* pessimism */
 467
 468        in = it->buf;
 469        while (in - it->buf <= it->len && (ep = strstr(in, "=?")) != NULL) {
 470                int encoding;
 471                strbuf_reset(&charset_q);
 472                strbuf_reset(&piecebuf);
 473
 474                if (in != ep) {
 475                        /*
 476                         * We are about to process an encoded-word
 477                         * that begins at ep, but there is something
 478                         * before the encoded word.
 479                         */
 480                        char *scan;
 481                        for (scan = in; scan < ep; scan++)
 482                                if (!isspace(*scan))
 483                                        break;
 484
 485                        if (scan != ep || in == it->buf) {
 486                                /*
 487                                 * We should not lose that "something",
 488                                 * unless we have just processed an
 489                                 * encoded-word, and there is only LWS
 490                                 * before the one we are about to process.
 491                                 */
 492                                strbuf_add(&outbuf, in, ep - in);
 493                        }
 494                }
 495                /* E.g.
 496                 * ep : "=?iso-2022-jp?B?GyR...?= foo"
 497                 * ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz"
 498                 */
 499                ep += 2;
 500
 501                if (ep - it->buf >= it->len || !(cp = strchr(ep, '?')))
 502                        goto release_return;
 503
 504                if (cp + 3 - it->buf > it->len)
 505                        goto release_return;
 506                strbuf_add(&charset_q, ep, cp - ep);
 507
 508                encoding = cp[1];
 509                if (!encoding || cp[2] != '?')
 510                        goto release_return;
 511                ep = strstr(cp + 3, "?=");
 512                if (!ep)
 513                        goto release_return;
 514                strbuf_add(&piecebuf, cp + 3, ep - cp - 3);
 515                switch (tolower(encoding)) {
 516                default:
 517                        goto release_return;
 518                case 'b':
 519                        dec = decode_b_segment(&piecebuf);
 520                        break;
 521                case 'q':
 522                        dec = decode_q_segment(&piecebuf, 1);
 523                        break;
 524                }
 525                if (convert_to_utf8(mi, dec, charset_q.buf))
 526                        goto release_return;
 527
 528                strbuf_addbuf(&outbuf, dec);
 529                strbuf_release(dec);
 530                free(dec);
 531                in = ep + 2;
 532        }
 533        strbuf_addstr(&outbuf, in);
 534        strbuf_reset(it);
 535        strbuf_addbuf(it, &outbuf);
 536        found_error = 0;
 537release_return:
 538        strbuf_release(&outbuf);
 539        strbuf_release(&charset_q);
 540        strbuf_release(&piecebuf);
 541
 542        if (found_error)
 543                mi->input_error = -1;
 544}
 545
 546static int check_header(struct mailinfo *mi,
 547                        const struct strbuf *line,
 548                        struct strbuf *hdr_data[], int overwrite)
 549{
 550        int i, ret = 0, len;
 551        struct strbuf sb = STRBUF_INIT;
 552
 553        /* search for the interesting parts */
 554        for (i = 0; header[i]; i++) {
 555                int len = strlen(header[i]);
 556                if ((!hdr_data[i] || overwrite) && cmp_header(line, header[i])) {
 557                        /* Unwrap inline B and Q encoding, and optionally
 558                         * normalize the meta information to utf8.
 559                         */
 560                        strbuf_add(&sb, line->buf + len + 2, line->len - len - 2);
 561                        decode_header(mi, &sb);
 562                        handle_header(&hdr_data[i], &sb);
 563                        ret = 1;
 564                        goto check_header_out;
 565                }
 566        }
 567
 568        /* Content stuff */
 569        if (cmp_header(line, "Content-Type")) {
 570                len = strlen("Content-Type: ");
 571                strbuf_add(&sb, line->buf + len, line->len - len);
 572                decode_header(mi, &sb);
 573                strbuf_insert(&sb, 0, "Content-Type: ", len);
 574                handle_content_type(mi, &sb);
 575                ret = 1;
 576                goto check_header_out;
 577        }
 578        if (cmp_header(line, "Content-Transfer-Encoding")) {
 579                len = strlen("Content-Transfer-Encoding: ");
 580                strbuf_add(&sb, line->buf + len, line->len - len);
 581                decode_header(mi, &sb);
 582                handle_content_transfer_encoding(mi, &sb);
 583                ret = 1;
 584                goto check_header_out;
 585        }
 586        if (cmp_header(line, "Message-Id")) {
 587                len = strlen("Message-Id: ");
 588                strbuf_add(&sb, line->buf + len, line->len - len);
 589                decode_header(mi, &sb);
 590                if (mi->add_message_id)
 591                        mi->message_id = strbuf_detach(&sb, NULL);
 592                ret = 1;
 593                goto check_header_out;
 594        }
 595
 596check_header_out:
 597        strbuf_release(&sb);
 598        return ret;
 599}
 600
 601/*
 602 * Returns 1 if the given line or any line beginning with the given line is an
 603 * in-body header (that is, check_header will succeed when passed
 604 * mi->s_hdr_data).
 605 */
 606static int is_inbody_header(const struct mailinfo *mi,
 607                            const struct strbuf *line)
 608{
 609        int i;
 610        for (i = 0; header[i]; i++)
 611                if (!mi->s_hdr_data[i] && cmp_header(line, header[i]))
 612                        return 1;
 613        return 0;
 614}
 615
 616static void decode_transfer_encoding(struct mailinfo *mi, struct strbuf *line)
 617{
 618        struct strbuf *ret;
 619
 620        switch (mi->transfer_encoding) {
 621        case TE_QP:
 622                ret = decode_q_segment(line, 0);
 623                break;
 624        case TE_BASE64:
 625                ret = decode_b_segment(line);
 626                break;
 627        case TE_DONTCARE:
 628        default:
 629                return;
 630        }
 631        strbuf_reset(line);
 632        strbuf_addbuf(line, ret);
 633        strbuf_release(ret);
 634        free(ret);
 635}
 636
 637static inline int patchbreak(const struct strbuf *line)
 638{
 639        size_t i;
 640
 641        /* Beginning of a "diff -" header? */
 642        if (starts_with(line->buf, "diff -"))
 643                return 1;
 644
 645        /* CVS "Index: " line? */
 646        if (starts_with(line->buf, "Index: "))
 647                return 1;
 648
 649        /*
 650         * "--- <filename>" starts patches without headers
 651         * "---<sp>*" is a manual separator
 652         */
 653        if (line->len < 4)
 654                return 0;
 655
 656        if (starts_with(line->buf, "---")) {
 657                /* space followed by a filename? */
 658                if (line->buf[3] == ' ' && !isspace(line->buf[4]))
 659                        return 1;
 660                /* Just whitespace? */
 661                for (i = 3; i < line->len; i++) {
 662                        unsigned char c = line->buf[i];
 663                        if (c == '\n')
 664                                return 1;
 665                        if (!isspace(c))
 666                                break;
 667                }
 668                return 0;
 669        }
 670        return 0;
 671}
 672
 673static int is_scissors_line(const char *line)
 674{
 675        const char *c;
 676        int scissors = 0, gap = 0;
 677        const char *first_nonblank = NULL, *last_nonblank = NULL;
 678        int visible, perforation = 0, in_perforation = 0;
 679
 680        for (c = line; *c; c++) {
 681                if (isspace(*c)) {
 682                        if (in_perforation) {
 683                                perforation++;
 684                                gap++;
 685                        }
 686                        continue;
 687                }
 688                last_nonblank = c;
 689                if (first_nonblank == NULL)
 690                        first_nonblank = c;
 691                if (*c == '-') {
 692                        in_perforation = 1;
 693                        perforation++;
 694                        continue;
 695                }
 696                if ((!memcmp(c, ">8", 2) || !memcmp(c, "8<", 2) ||
 697                     !memcmp(c, ">%", 2) || !memcmp(c, "%<", 2))) {
 698                        in_perforation = 1;
 699                        perforation += 2;
 700                        scissors += 2;
 701                        c++;
 702                        continue;
 703                }
 704                in_perforation = 0;
 705        }
 706
 707        /*
 708         * The mark must be at least 8 bytes long (e.g. "-- >8 --").
 709         * Even though there can be arbitrary cruft on the same line
 710         * (e.g. "cut here"), in order to avoid misidentification, the
 711         * perforation must occupy more than a third of the visible
 712         * width of the line, and dashes and scissors must occupy more
 713         * than half of the perforation.
 714         */
 715
 716        if (first_nonblank && last_nonblank)
 717                visible = last_nonblank - first_nonblank + 1;
 718        else
 719                visible = 0;
 720        return (scissors && 8 <= visible &&
 721                visible < perforation * 3 &&
 722                gap * 2 < perforation);
 723}
 724
 725static void flush_inbody_header_accum(struct mailinfo *mi)
 726{
 727        if (!mi->inbody_header_accum.len)
 728                return;
 729        if (!check_header(mi, &mi->inbody_header_accum, mi->s_hdr_data, 0))
 730                BUG("inbody_header_accum, if not empty, must always contain a valid in-body header");
 731        strbuf_reset(&mi->inbody_header_accum);
 732}
 733
 734static int check_inbody_header(struct mailinfo *mi, const struct strbuf *line)
 735{
 736        if (mi->inbody_header_accum.len &&
 737            (line->buf[0] == ' ' || line->buf[0] == '\t')) {
 738                if (mi->use_scissors && is_scissors_line(line->buf)) {
 739                        /*
 740                         * This is a scissors line; do not consider this line
 741                         * as a header continuation line.
 742                         */
 743                        flush_inbody_header_accum(mi);
 744                        return 0;
 745                }
 746                strbuf_strip_suffix(&mi->inbody_header_accum, "\n");
 747                strbuf_addbuf(&mi->inbody_header_accum, line);
 748                return 1;
 749        }
 750
 751        flush_inbody_header_accum(mi);
 752
 753        if (starts_with(line->buf, ">From") && isspace(line->buf[5]))
 754                return is_format_patch_separator(line->buf + 1, line->len - 1);
 755        if (starts_with(line->buf, "[PATCH]") && isspace(line->buf[7])) {
 756                int i;
 757                for (i = 0; header[i]; i++)
 758                        if (!strcmp("Subject", header[i])) {
 759                                handle_header(&mi->s_hdr_data[i], line);
 760                                return 1;
 761                        }
 762                return 0;
 763        }
 764        if (is_inbody_header(mi, line)) {
 765                strbuf_addbuf(&mi->inbody_header_accum, line);
 766                return 1;
 767        }
 768        return 0;
 769}
 770
 771static int handle_commit_msg(struct mailinfo *mi, struct strbuf *line)
 772{
 773        assert(!mi->filter_stage);
 774
 775        if (mi->header_stage) {
 776                if (!line->len || (line->len == 1 && line->buf[0] == '\n')) {
 777                        if (mi->inbody_header_accum.len) {
 778                                flush_inbody_header_accum(mi);
 779                                mi->header_stage = 0;
 780                        }
 781                        return 0;
 782                }
 783        }
 784
 785        if (mi->use_inbody_headers && mi->header_stage) {
 786                mi->header_stage = check_inbody_header(mi, line);
 787                if (mi->header_stage)
 788                        return 0;
 789        } else
 790                /* Only trim the first (blank) line of the commit message
 791                 * when ignoring in-body headers.
 792                 */
 793                mi->header_stage = 0;
 794
 795        /* normalize the log message to UTF-8. */
 796        if (convert_to_utf8(mi, line, mi->charset.buf))
 797                return 0; /* mi->input_error already set */
 798
 799        if (mi->use_scissors && is_scissors_line(line->buf)) {
 800                int i;
 801
 802                strbuf_setlen(&mi->log_message, 0);
 803                mi->header_stage = 1;
 804
 805                /*
 806                 * We may have already read "secondary headers"; purge
 807                 * them to give ourselves a clean restart.
 808                 */
 809                for (i = 0; header[i]; i++) {
 810                        if (mi->s_hdr_data[i])
 811                                strbuf_release(mi->s_hdr_data[i]);
 812                        mi->s_hdr_data[i] = NULL;
 813                }
 814                return 0;
 815        }
 816
 817        if (patchbreak(line)) {
 818                if (mi->message_id)
 819                        strbuf_addf(&mi->log_message,
 820                                    "Message-Id: %s\n", mi->message_id);
 821                return 1;
 822        }
 823
 824        strbuf_addbuf(&mi->log_message, line);
 825        return 0;
 826}
 827
 828static void handle_patch(struct mailinfo *mi, const struct strbuf *line)
 829{
 830        fwrite(line->buf, 1, line->len, mi->patchfile);
 831        mi->patch_lines++;
 832}
 833
 834static void handle_filter(struct mailinfo *mi, struct strbuf *line)
 835{
 836        switch (mi->filter_stage) {
 837        case 0:
 838                if (!handle_commit_msg(mi, line))
 839                        break;
 840                mi->filter_stage++;
 841                /* fallthrough */
 842        case 1:
 843                handle_patch(mi, line);
 844                break;
 845        }
 846}
 847
 848static int is_rfc2822_header(const struct strbuf *line)
 849{
 850        /*
 851         * The section that defines the loosest possible
 852         * field name is "3.6.8 Optional fields".
 853         *
 854         * optional-field = field-name ":" unstructured CRLF
 855         * field-name = 1*ftext
 856         * ftext = %d33-57 / %59-126
 857         */
 858        int ch;
 859        char *cp = line->buf;
 860
 861        /* Count mbox From headers as headers */
 862        if (starts_with(cp, "From ") || starts_with(cp, ">From "))
 863                return 1;
 864
 865        while ((ch = *cp++)) {
 866                if (ch == ':')
 867                        return 1;
 868                if ((33 <= ch && ch <= 57) ||
 869                    (59 <= ch && ch <= 126))
 870                        continue;
 871                break;
 872        }
 873        return 0;
 874}
 875
 876static int read_one_header_line(struct strbuf *line, FILE *in)
 877{
 878        struct strbuf continuation = STRBUF_INIT;
 879
 880        /* Get the first part of the line. */
 881        if (strbuf_getline_lf(line, in))
 882                return 0;
 883
 884        /*
 885         * Is it an empty line or not a valid rfc2822 header?
 886         * If so, stop here, and return false ("not a header")
 887         */
 888        strbuf_rtrim(line);
 889        if (!line->len || !is_rfc2822_header(line)) {
 890                /* Re-add the newline */
 891                strbuf_addch(line, '\n');
 892                return 0;
 893        }
 894
 895        /*
 896         * Now we need to eat all the continuation lines..
 897         * Yuck, 2822 header "folding"
 898         */
 899        for (;;) {
 900                int peek;
 901
 902                peek = fgetc(in);
 903                if (peek == EOF)
 904                        break;
 905                ungetc(peek, in);
 906                if (peek != ' ' && peek != '\t')
 907                        break;
 908                if (strbuf_getline_lf(&continuation, in))
 909                        break;
 910                continuation.buf[0] = ' ';
 911                strbuf_rtrim(&continuation);
 912                strbuf_addbuf(line, &continuation);
 913        }
 914        strbuf_release(&continuation);
 915
 916        return 1;
 917}
 918
 919static int find_boundary(struct mailinfo *mi, struct strbuf *line)
 920{
 921        while (!strbuf_getline_lf(line, mi->input)) {
 922                if (*(mi->content_top) && is_multipart_boundary(mi, line))
 923                        return 1;
 924        }
 925        return 0;
 926}
 927
 928static int handle_boundary(struct mailinfo *mi, struct strbuf *line)
 929{
 930        struct strbuf newline = STRBUF_INIT;
 931
 932        strbuf_addch(&newline, '\n');
 933again:
 934        if (line->len >= (*(mi->content_top))->len + 2 &&
 935            !memcmp(line->buf + (*(mi->content_top))->len, "--", 2)) {
 936                /* we hit an end boundary */
 937                /* pop the current boundary off the stack */
 938                strbuf_release(*(mi->content_top));
 939                FREE_AND_NULL(*(mi->content_top));
 940
 941                /* technically won't happen as is_multipart_boundary()
 942                   will fail first.  But just in case..
 943                 */
 944                if (--mi->content_top < mi->content) {
 945                        error("Detected mismatched boundaries, can't recover");
 946                        mi->input_error = -1;
 947                        mi->content_top = mi->content;
 948                        strbuf_release(&newline);
 949                        return 0;
 950                }
 951                handle_filter(mi, &newline);
 952                strbuf_release(&newline);
 953                if (mi->input_error)
 954                        return 0;
 955
 956                /* skip to the next boundary */
 957                if (!find_boundary(mi, line))
 958                        return 0;
 959                goto again;
 960        }
 961
 962        /* set some defaults */
 963        mi->transfer_encoding = TE_DONTCARE;
 964        strbuf_reset(&mi->charset);
 965
 966        /* slurp in this section's info */
 967        while (read_one_header_line(line, mi->input))
 968                check_header(mi, line, mi->p_hdr_data, 0);
 969
 970        strbuf_release(&newline);
 971        /* replenish line */
 972        if (strbuf_getline_lf(line, mi->input))
 973                return 0;
 974        strbuf_addch(line, '\n');
 975        return 1;
 976}
 977
 978static void handle_filter_flowed(struct mailinfo *mi, struct strbuf *line,
 979                                 struct strbuf *prev)
 980{
 981        size_t len = line->len;
 982        const char *rest;
 983
 984        if (!mi->format_flowed) {
 985                handle_filter(mi, line);
 986                return;
 987        }
 988
 989        if (line->buf[len - 1] == '\n') {
 990                len--;
 991                if (len && line->buf[len - 1] == '\r')
 992                        len--;
 993        }
 994
 995        /* Keep signature separator as-is. */
 996        if (skip_prefix(line->buf, "-- ", &rest) && rest - line->buf == len) {
 997                if (prev->len) {
 998                        handle_filter(mi, prev);
 999                        strbuf_reset(prev);
1000                }
1001                handle_filter(mi, line);
1002                return;
1003        }
1004
1005        /* Unstuff space-stuffed line. */
1006        if (len && line->buf[0] == ' ') {
1007                strbuf_remove(line, 0, 1);
1008                len--;
1009        }
1010
1011        /* Save flowed line for later, but without the soft line break. */
1012        if (len && line->buf[len - 1] == ' ') {
1013                strbuf_add(prev, line->buf, len - !!mi->delsp);
1014                return;
1015        }
1016
1017        /* Prepend any previous partial lines */
1018        strbuf_insert(line, 0, prev->buf, prev->len);
1019        strbuf_reset(prev);
1020
1021        handle_filter(mi, line);
1022}
1023
1024static void handle_body(struct mailinfo *mi, struct strbuf *line)
1025{
1026        struct strbuf prev = STRBUF_INIT;
1027
1028        /* Skip up to the first boundary */
1029        if (*(mi->content_top)) {
1030                if (!find_boundary(mi, line))
1031                        goto handle_body_out;
1032        }
1033
1034        do {
1035                /* process any boundary lines */
1036                if (*(mi->content_top) && is_multipart_boundary(mi, line)) {
1037                        /* flush any leftover */
1038                        if (prev.len) {
1039                                handle_filter(mi, &prev);
1040                                strbuf_reset(&prev);
1041                        }
1042                        if (!handle_boundary(mi, line))
1043                                goto handle_body_out;
1044                }
1045
1046                /* Unwrap transfer encoding */
1047                decode_transfer_encoding(mi, line);
1048
1049                switch (mi->transfer_encoding) {
1050                case TE_BASE64:
1051                case TE_QP:
1052                {
1053                        struct strbuf **lines, **it, *sb;
1054
1055                        /* Prepend any previous partial lines */
1056                        strbuf_insert(line, 0, prev.buf, prev.len);
1057                        strbuf_reset(&prev);
1058
1059                        /*
1060                         * This is a decoded line that may contain
1061                         * multiple new lines.  Pass only one chunk
1062                         * at a time to handle_filter()
1063                         */
1064                        lines = strbuf_split(line, '\n');
1065                        for (it = lines; (sb = *it); it++) {
1066                                if (*(it + 1) == NULL) /* The last line */
1067                                        if (sb->buf[sb->len - 1] != '\n') {
1068                                                /* Partial line, save it for later. */
1069                                                strbuf_addbuf(&prev, sb);
1070                                                break;
1071                                        }
1072                                handle_filter_flowed(mi, sb, &prev);
1073                        }
1074                        /*
1075                         * The partial chunk is saved in "prev" and will be
1076                         * appended by the next iteration of read_line_with_nul().
1077                         */
1078                        strbuf_list_free(lines);
1079                        break;
1080                }
1081                default:
1082                        handle_filter_flowed(mi, line, &prev);
1083                }
1084
1085                if (mi->input_error)
1086                        break;
1087        } while (!strbuf_getwholeline(line, mi->input, '\n'));
1088
1089        if (prev.len)
1090                handle_filter(mi, &prev);
1091
1092        flush_inbody_header_accum(mi);
1093
1094handle_body_out:
1095        strbuf_release(&prev);
1096}
1097
1098static void output_header_lines(FILE *fout, const char *hdr, const struct strbuf *data)
1099{
1100        const char *sp = data->buf;
1101        while (1) {
1102                char *ep = strchr(sp, '\n');
1103                int len;
1104                if (!ep)
1105                        len = strlen(sp);
1106                else
1107                        len = ep - sp;
1108                fprintf(fout, "%s: %.*s\n", hdr, len, sp);
1109                if (!ep)
1110                        break;
1111                sp = ep + 1;
1112        }
1113}
1114
1115static void handle_info(struct mailinfo *mi)
1116{
1117        struct strbuf *hdr;
1118        int i;
1119
1120        for (i = 0; header[i]; i++) {
1121                /* only print inbody headers if we output a patch file */
1122                if (mi->patch_lines && mi->s_hdr_data[i])
1123                        hdr = mi->s_hdr_data[i];
1124                else if (mi->p_hdr_data[i])
1125                        hdr = mi->p_hdr_data[i];
1126                else
1127                        continue;
1128
1129                if (!strcmp(header[i], "Subject")) {
1130                        if (!mi->keep_subject) {
1131                                cleanup_subject(mi, hdr);
1132                                cleanup_space(hdr);
1133                        }
1134                        output_header_lines(mi->output, "Subject", hdr);
1135                } else if (!strcmp(header[i], "From")) {
1136                        cleanup_space(hdr);
1137                        handle_from(mi, hdr);
1138                        fprintf(mi->output, "Author: %s\n", mi->name.buf);
1139                        fprintf(mi->output, "Email: %s\n", mi->email.buf);
1140                } else {
1141                        cleanup_space(hdr);
1142                        fprintf(mi->output, "%s: %s\n", header[i], hdr->buf);
1143                }
1144        }
1145        fprintf(mi->output, "\n");
1146}
1147
1148int mailinfo(struct mailinfo *mi, const char *msg, const char *patch)
1149{
1150        FILE *cmitmsg;
1151        int peek;
1152        struct strbuf line = STRBUF_INIT;
1153
1154        cmitmsg = fopen(msg, "w");
1155        if (!cmitmsg) {
1156                perror(msg);
1157                return -1;
1158        }
1159        mi->patchfile = fopen(patch, "w");
1160        if (!mi->patchfile) {
1161                perror(patch);
1162                fclose(cmitmsg);
1163                return -1;
1164        }
1165
1166        mi->p_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->p_hdr_data)));
1167        mi->s_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(*(mi->s_hdr_data)));
1168
1169        do {
1170                peek = fgetc(mi->input);
1171                if (peek == EOF) {
1172                        fclose(cmitmsg);
1173                        return error("empty patch: '%s'", patch);
1174                }
1175        } while (isspace(peek));
1176        ungetc(peek, mi->input);
1177
1178        /* process the email header */
1179        while (read_one_header_line(&line, mi->input))
1180                check_header(mi, &line, mi->p_hdr_data, 1);
1181
1182        handle_body(mi, &line);
1183        fwrite(mi->log_message.buf, 1, mi->log_message.len, cmitmsg);
1184        fclose(cmitmsg);
1185        fclose(mi->patchfile);
1186
1187        handle_info(mi);
1188        strbuf_release(&line);
1189        return mi->input_error;
1190}
1191
1192static int git_mailinfo_config(const char *var, const char *value, void *mi_)
1193{
1194        struct mailinfo *mi = mi_;
1195
1196        if (!starts_with(var, "mailinfo."))
1197                return git_default_config(var, value, NULL);
1198        if (!strcmp(var, "mailinfo.scissors")) {
1199                mi->use_scissors = git_config_bool(var, value);
1200                return 0;
1201        }
1202        /* perhaps others here */
1203        return 0;
1204}
1205
1206void setup_mailinfo(struct mailinfo *mi)
1207{
1208        memset(mi, 0, sizeof(*mi));
1209        strbuf_init(&mi->name, 0);
1210        strbuf_init(&mi->email, 0);
1211        strbuf_init(&mi->charset, 0);
1212        strbuf_init(&mi->log_message, 0);
1213        strbuf_init(&mi->inbody_header_accum, 0);
1214        mi->header_stage = 1;
1215        mi->use_inbody_headers = 1;
1216        mi->content_top = mi->content;
1217        git_config(git_mailinfo_config, mi);
1218}
1219
1220void clear_mailinfo(struct mailinfo *mi)
1221{
1222        int i;
1223
1224        strbuf_release(&mi->name);
1225        strbuf_release(&mi->email);
1226        strbuf_release(&mi->charset);
1227        strbuf_release(&mi->inbody_header_accum);
1228        free(mi->message_id);
1229
1230        if (mi->p_hdr_data)
1231                for (i = 0; mi->p_hdr_data[i]; i++)
1232                        strbuf_release(mi->p_hdr_data[i]);
1233        free(mi->p_hdr_data);
1234        if (mi->s_hdr_data)
1235                for (i = 0; mi->s_hdr_data[i]; i++)
1236                        strbuf_release(mi->s_hdr_data[i]);
1237        free(mi->s_hdr_data);
1238
1239        while (mi->content < mi->content_top) {
1240                free(*(mi->content_top));
1241                mi->content_top--;
1242        }
1243
1244        strbuf_release(&mi->log_message);
1245}