diff options
Diffstat (limited to 'mailinfo.c')
| -rw-r--r-- | mailinfo.c | 749 |
1 files changed, 749 insertions, 0 deletions
diff --git a/mailinfo.c b/mailinfo.c new file mode 100644 index 0000000000..df470bb9c2 --- /dev/null +++ b/mailinfo.c @@ -0,0 +1,749 @@ +/* + * Another stupid program, this one parsing the headers of an + * email to figure out authorship and subject + */ +#define _GNU_SOURCE +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <ctype.h> +#include <iconv.h> + +static FILE *cmitmsg, *patchfile; + +static int keep_subject = 0; +static int metainfo_utf8 = 0; +static char line[1000]; +static char date[1000]; +static char name[1000]; +static char email[1000]; +static char subject[1000]; + +static enum { + TE_DONTCARE, TE_QP, TE_BASE64, +} transfer_encoding; +static char charset[256]; + +static char multipart_boundary[1000]; +static int multipart_boundary_len; +static int patch_lines = 0; + +static char *sanity_check(char *name, char *email) +{ + int len = strlen(name); + if (len < 3 || len > 60) + return email; + if (strchr(name, '@') || strchr(name, '<') || strchr(name, '>')) + return email; + return name; +} + +static int handle_from(char *line) +{ + char *at = strchr(line, '@'); + char *dst; + + if (!at) + return 0; + + /* + * If we already have one email, don't take any confusing lines + */ + if (*email && strchr(at+1, '@')) + return 0; + + /* Pick up the string around '@', possibly delimited with <> + * pair; that is the email part. White them out while copying. + */ + while (at > line) { + char c = at[-1]; + if (isspace(c)) + break; + if (c == '<') { + at[-1] = ' '; + break; + } + at--; + } + dst = email; + for (;;) { + unsigned char c = *at; + if (!c || c == '>' || isspace(c)) { + if (c == '>') + *at = ' '; + break; + } + *at++ = ' '; + *dst++ = c; + } + *dst++ = 0; + + /* The remainder is name. It could be "John Doe <john.doe@xz>" + * or "john.doe@xz (John Doe)", but we have whited out the + * email part, so trim from both ends, possibly removing + * the () pair at the end. + */ + at = line + strlen(line); + while (at > line) { + unsigned char c = *--at; + if (!isspace(c)) { + at[(c == ')') ? 0 : 1] = 0; + break; + } + } + + at = line; + for (;;) { + unsigned char c = *at; + if (!c || !isspace(c)) { + if (c == '(') + at++; + break; + } + at++; + } + at = sanity_check(at, email); + strcpy(name, at); + return 1; +} + +static int handle_date(char *line) +{ + strcpy(date, line); + return 0; +} + +static int handle_subject(char *line) +{ + strcpy(subject, line); + return 0; +} + +/* NOTE NOTE NOTE. We do not claim we do full MIME. We just attempt + * to have enough heuristics to grok MIME encoded patches often found + * on our mailing lists. For example, we do not even treat header lines + * case insensitively. + */ + +static int slurp_attr(const char *line, const char *name, char *attr) +{ + char *ends, *ap = strcasestr(line, name); + size_t sz; + + if (!ap) { + *attr = 0; + return 0; + } + ap += strlen(name); + if (*ap == '"') { + ap++; + ends = "\""; + } + else + ends = "; \t"; + sz = strcspn(ap, ends); + memcpy(attr, ap, sz); + attr[sz] = 0; + return 1; +} + +static int handle_subcontent_type(char *line) +{ + /* We do not want to mess with boundary. Note that we do not + * handle nested multipart. + */ + if (strcasestr(line, "boundary=")) { + fprintf(stderr, "Not handling nested multipart message.\n"); + exit(1); + } + slurp_attr(line, "charset=", charset); + if (*charset) { + int i, c; + for (i = 0; (c = charset[i]) != 0; i++) + charset[i] = tolower(c); + } + return 0; +} + +static int handle_content_type(char *line) +{ + *multipart_boundary = 0; + if (slurp_attr(line, "boundary=", multipart_boundary + 2)) { + memcpy(multipart_boundary, "--", 2); + multipart_boundary_len = strlen(multipart_boundary); + } + slurp_attr(line, "charset=", charset); + return 0; +} + +static int handle_content_transfer_encoding(char *line) +{ + if (strcasestr(line, "base64")) + transfer_encoding = TE_BASE64; + else if (strcasestr(line, "quoted-printable")) + transfer_encoding = TE_QP; + else + transfer_encoding = TE_DONTCARE; + return 0; +} + +static int is_multipart_boundary(const char *line) +{ + return (!memcmp(line, multipart_boundary, multipart_boundary_len)); +} + +static int eatspace(char *line) +{ + int len = strlen(line); + while (len > 0 && isspace(line[len-1])) + line[--len] = 0; + return len; +} + +#define SEEN_FROM 01 +#define SEEN_DATE 02 +#define SEEN_SUBJECT 04 + +/* First lines of body can have From:, Date:, and Subject: */ +static int handle_inbody_header(int *seen, char *line) +{ + if (!memcmp("From:", line, 5) && isspace(line[5])) { + if (!(*seen & SEEN_FROM) && handle_from(line+6)) { + *seen |= SEEN_FROM; + return 1; + } + } + if (!memcmp("Date:", line, 5) && isspace(line[5])) { + if (!(*seen & SEEN_DATE)) { + handle_date(line+6); + *seen |= SEEN_DATE; + return 1; + } + } + if (!memcmp("Subject:", line, 8) && isspace(line[8])) { + if (!(*seen & SEEN_SUBJECT)) { + handle_subject(line+9); + *seen |= SEEN_SUBJECT; + return 1; + } + } + if (!memcmp("[PATCH]", line, 7) && isspace(line[7])) { + if (!(*seen & SEEN_SUBJECT)) { + handle_subject(line); + *seen |= SEEN_SUBJECT; + return 1; + } + } + return 0; +} + +static char *cleanup_subject(char *subject) +{ + if (keep_subject) + return subject; + for (;;) { + char *p; + int len, remove; + switch (*subject) { + case 'r': case 'R': + if (!memcmp("e:", subject+1, 2)) { + subject +=3; + continue; + } + break; + case ' ': case '\t': case ':': + subject++; + continue; + + case '[': + p = strchr(subject, ']'); + if (!p) { + subject++; + continue; + } + len = strlen(p); + remove = p - subject; + if (remove <= len *2) { + subject = p+1; + continue; + } + break; + } + return subject; + } +} + +static void cleanup_space(char *buf) +{ + unsigned char c; + while ((c = *buf) != 0) { + buf++; + if (isspace(c)) { + buf[-1] = ' '; + c = *buf; + while (isspace(c)) { + int len = strlen(buf); + memmove(buf, buf+1, len); + c = *buf; + } + } + } +} + +typedef int (*header_fn_t)(char *); +struct header_def { + const char *name; + header_fn_t func; + int namelen; +}; + +static void check_header(char *line, int len, struct header_def *header) +{ + int i; + + if (header[0].namelen <= 0) { + for (i = 0; header[i].name; i++) + header[i].namelen = strlen(header[i].name); + } + for (i = 0; header[i].name; i++) { + int len = header[i].namelen; + if (!strncasecmp(line, header[i].name, len) && + line[len] == ':' && isspace(line[len + 1])) { + header[i].func(line + len + 2); + break; + } + } +} + +static void check_subheader_line(char *line, int len) +{ + static struct header_def header[] = { + { "Content-Type", handle_subcontent_type }, + { "Content-Transfer-Encoding", + handle_content_transfer_encoding }, + { NULL }, + }; + check_header(line, len, header); +} +static void check_header_line(char *line, int len) +{ + static struct header_def header[] = { + { "From", handle_from }, + { "Date", handle_date }, + { "Subject", handle_subject }, + { "Content-Type", handle_content_type }, + { "Content-Transfer-Encoding", + handle_content_transfer_encoding }, + { NULL }, + }; + check_header(line, len, header); +} + +static int read_one_header_line(char *line, int sz, FILE *in) +{ + int ofs = 0; + while (ofs < sz) { + int peek, len; + if (fgets(line + ofs, sz - ofs, in) == NULL) + return ofs; + len = eatspace(line + ofs); + if (len == 0) + return ofs; + peek = fgetc(in); ungetc(peek, in); + if (peek == ' ' || peek == '\t') { + /* Yuck, 2822 header "folding" */ + ofs += len; + continue; + } + return ofs + len; + } + return ofs; +} + +static unsigned hexval(int c) +{ + if (c >= '0' && c <= '9') + return c - '0'; + if (c >= 'a' && c <= 'f') + return c - 'a' + 10; + if (c >= 'A' && c <= 'F') + return c - 'A' + 10; + return ~0; +} + +static int decode_q_segment(char *in, char *ot, char *ep) +{ + int c; + while ((c = *in++) != 0 && (in <= ep)) { + if (c == '=') { + int d = *in++; + if (d == '\n' || !d) + break; /* drop trailing newline */ + *ot++ = ((hexval(d) << 4) | hexval(*in++)); + } + else + *ot++ = c; + } + *ot = 0; + return 0; +} + +static int decode_b_segment(char *in, char *ot, char *ep) +{ + /* Decode in..ep, possibly in-place to ot */ + int c, pos = 0, acc = 0; + + while ((c = *in++) != 0 && (in <= ep)) { + if (c == '+') + c = 62; + else if (c == '/') + c = 63; + else if ('A' <= c && c <= 'Z') + c -= 'A'; + else if ('a' <= c && c <= 'z') + c -= 'a' - 26; + else if ('0' <= c && c <= '9') + c -= '0' - 52; + else if (c == '=') { + /* padding is almost like (c == 0), except we do + * not output NUL resulting only from it; + * for now we just trust the data. + */ + c = 0; + } + else + continue; /* garbage */ + switch (pos++) { + case 0: + acc = (c << 2); + break; + case 1: + *ot++ = (acc | (c >> 4)); + acc = (c & 15) << 4; + break; + case 2: + *ot++ = (acc | (c >> 2)); + acc = (c & 3) << 6; + break; + case 3: + *ot++ = (acc | c); + acc = pos = 0; + break; + } + } + *ot = 0; + return 0; +} + +static void convert_to_utf8(char *line, char *charset) +{ + if (*charset) { + char *in, *out; + size_t insize, outsize, nrc; + char outbuf[4096]; /* cheat */ + iconv_t conv = iconv_open("utf-8", charset); + + if (conv == (iconv_t) -1) { + fprintf(stderr, "cannot convert from %s to utf-8\n", + charset); + *charset = 0; + return; + } + in = line; + insize = strlen(in); + out = outbuf; + outsize = sizeof(outbuf); + nrc = iconv(conv, &in, &insize, &out, &outsize); + iconv_close(conv); + if (nrc == (size_t) -1) + return; + *out = 0; + strcpy(line, outbuf); + } +} + +static void decode_header_bq(char *it) +{ + char *in, *out, *ep, *cp, *sp; + char outbuf[1000]; + + in = it; + out = outbuf; + while ((ep = strstr(in, "=?")) != NULL) { + int sz, encoding; + char charset_q[256], piecebuf[256]; + if (in != ep) { + sz = ep - in; + memcpy(out, in, sz); + out += sz; + in += sz; + } + /* E.g. + * ep : "=?iso-2022-jp?B?GyR...?= foo" + * ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz" + */ + ep += 2; + cp = strchr(ep, '?'); + if (!cp) + return; /* no munging */ + for (sp = ep; sp < cp; sp++) + charset_q[sp - ep] = tolower(*sp); + charset_q[cp - ep] = 0; + encoding = cp[1]; + if (!encoding || cp[2] != '?') + return; /* no munging */ + ep = strstr(cp + 3, "?="); + if (!ep) + return; /* no munging */ + switch (tolower(encoding)) { + default: + return; /* no munging */ + case 'b': + sz = decode_b_segment(cp + 3, piecebuf, ep); + break; + case 'q': + sz = decode_q_segment(cp + 3, piecebuf, ep); + break; + } + if (sz < 0) + return; + if (metainfo_utf8) + convert_to_utf8(piecebuf, charset_q); + strcpy(out, piecebuf); + out += strlen(out); + in = ep + 2; + } + strcpy(out, in); + strcpy(it, outbuf); +} + +static void decode_transfer_encoding(char *line) +{ + char *ep; + + switch (transfer_encoding) { + case TE_QP: + ep = line + strlen(line); + decode_q_segment(line, line, ep); + break; + case TE_BASE64: + ep = line + strlen(line); + decode_b_segment(line, line, ep); + break; + case TE_DONTCARE: + break; + } +} + +static void handle_info(void) +{ + char *sub; + static int done_info = 0; + + if (done_info) + return; + + done_info = 1; + sub = cleanup_subject(subject); + cleanup_space(name); + cleanup_space(date); + cleanup_space(email); + cleanup_space(sub); + + /* Unwrap inline B and Q encoding, and optionally + * normalize the meta information to utf8. + */ + decode_header_bq(name); + decode_header_bq(date); + decode_header_bq(email); + decode_header_bq(sub); + printf("Author: %s\nEmail: %s\nSubject: %s\nDate: %s\n\n", + name, email, sub, date); +} + +/* We are inside message body and have read line[] already. + * Spit out the commit log. + */ +static int handle_commit_msg(void) +{ + if (!cmitmsg) + return 0; + do { + if (!memcmp("diff -", line, 6) || + !memcmp("---", line, 3) || + !memcmp("Index: ", line, 7)) + break; + if ((multipart_boundary[0] && is_multipart_boundary(line))) { + /* We come here when the first part had only + * the commit message without any patch. We + * pretend we have not seen this line yet, and + * go back to the loop. + */ + return 1; + } + + /* Unwrap transfer encoding and optionally + * normalize the log message to UTF-8. + */ + decode_transfer_encoding(line); + if (metainfo_utf8) + convert_to_utf8(line, charset); + fputs(line, cmitmsg); + } while (fgets(line, sizeof(line), stdin) != NULL); + fclose(cmitmsg); + cmitmsg = NULL; + return 0; +} + +/* We have done the commit message and have the first + * line of the patch in line[]. + */ +static void handle_patch(void) +{ + do { + if (multipart_boundary[0] && is_multipart_boundary(line)) + break; + /* Only unwrap transfer encoding but otherwise do not + * do anything. We do *NOT* want UTF-8 conversion + * here; we are dealing with the user payload. + */ + decode_transfer_encoding(line); + fputs(line, patchfile); + patch_lines++; + } while (fgets(line, sizeof(line), stdin) != NULL); +} + +/* multipart boundary and transfer encoding are set up for us, and we + * are at the end of the sub header. do equivalent of handle_body up + * to the next boundary without closing patchfile --- we will expect + * that the first part to contain commit message and a patch, and + * handle other parts as pure patches. + */ +static int handle_multipart_one_part(void) +{ + int seen = 0; + int n = 0; + int len; + + while (fgets(line, sizeof(line), stdin) != NULL) { + again: + len = eatspace(line); + n++; + if (!len) + continue; + if (is_multipart_boundary(line)) + break; + if (0 <= seen && handle_inbody_header(&seen, line)) + continue; + seen = -1; /* no more inbody headers */ + line[len] = '\n'; + handle_info(); + if (handle_commit_msg()) + goto again; + handle_patch(); + break; + } + if (n == 0) + return -1; + return 0; +} + +static void handle_multipart_body(void) +{ + int part_num = 0; + + /* Skip up to the first boundary */ + while (fgets(line, sizeof(line), stdin) != NULL) + if (is_multipart_boundary(line)) { + part_num = 1; + break; + } + if (!part_num) + return; + /* We are on boundary line. Start slurping the subhead. */ + while (1) { + int len = read_one_header_line(line, sizeof(line), stdin); + if (!len) { + if (handle_multipart_one_part() < 0) + return; + } + else + check_subheader_line(line, len); + } + fclose(patchfile); + if (!patch_lines) { + fprintf(stderr, "No patch found\n"); + exit(1); + } +} + +/* Non multipart message */ +static void handle_body(void) +{ + int seen = 0; + + while (fgets(line, sizeof(line), stdin) != NULL) { + int len = eatspace(line); + if (!len) + continue; + if (0 <= seen && handle_inbody_header(&seen, line)) + continue; + seen = -1; /* no more inbody headers */ + line[len] = '\n'; + handle_info(); + handle_commit_msg(); + handle_patch(); + break; + } + fclose(patchfile); + if (!patch_lines) { + fprintf(stderr, "No patch found\n"); + exit(1); + } +} + +static const char mailinfo_usage[] = + "git-mailinfo [-k] [-u] msg patch <mail >info"; + +static void usage(void) { + fprintf(stderr, "%s\n", mailinfo_usage); + exit(1); +} + +int main(int argc, char **argv) +{ + while (1 < argc && argv[1][0] == '-') { + if (!strcmp(argv[1], "-k")) + keep_subject = 1; + else if (!strcmp(argv[1], "-u")) + metainfo_utf8 = 1; + else + usage(); + argc--; argv++; + } + + if (argc != 3) + usage(); + cmitmsg = fopen(argv[1], "w"); + if (!cmitmsg) { + perror(argv[1]); + exit(1); + } + patchfile = fopen(argv[2], "w"); + if (!patchfile) { + perror(argv[2]); + exit(1); + } + while (1) { + int len = read_one_header_line(line, sizeof(line), stdin); + if (!len) { + if (multipart_boundary[0]) + handle_multipart_body(); + else + handle_body(); + break; + } + check_header_line(line, len); + } + return 0; +} |