git/mailinfo.c

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/*
* 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>
#ifndef NO_ICONV
#include <iconv.h>
#endif
#include "git-compat-util.h"
#include "cache.h"
static FILE *cmitmsg, *patchfile;
static int keep_subject = 0;
static char *metainfo_charset = NULL;
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 bogus_from(char *line)
{
/* John Doe <johndoe> */
char *bra, *ket, *dst, *cp;
/* This is fallback, so do not bother if we already have an
* e-mail address.
*/
if (*email)
return 0;
bra = strchr(line, '<');
if (!bra)
return 0;
ket = strchr(bra, '>');
if (!ket)
return 0;
for (dst = email, cp = bra+1; cp < ket; )
*dst++ = *cp++;
*dst = 0;
for (cp = line; isspace(*cp); cp++)
;
for (bra--; isspace(*bra); bra--)
*bra = 0;
cp = sanity_check(cp, email);
strcpy(name, cp);
return 1;
}
static int handle_from(char *in_line)
{
char line[1000];
char *at;
char *dst;
strcpy(line, in_line);
at = strchr(line, '@');
if (!at)
return bogus_from(line);
/*
* 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
#define SEEN_BOGUS_UNIX_FROM 010
#define SEEN_PREFIX 020
/* First lines of body can have From:, Date:, and Subject: */
static void handle_inbody_header(int *seen, char *line)
{
if (*seen & SEEN_PREFIX)
return;
if (!memcmp(">From", line, 5) && isspace(line[5])) {
if (!(*seen & SEEN_BOGUS_UNIX_FROM)) {
*seen |= SEEN_BOGUS_UNIX_FROM;
return;
}
}
if (!memcmp("From:", line, 5) && isspace(line[5])) {
if (!(*seen & SEEN_FROM) && handle_from(line+6)) {
*seen |= SEEN_FROM;
return;
}
}
if (!memcmp("Date:", line, 5) && isspace(line[5])) {
if (!(*seen & SEEN_DATE)) {
handle_date(line+6);
*seen |= SEEN_DATE;
return;
}
}
if (!memcmp("Subject:", line, 8) && isspace(line[8])) {
if (!(*seen & SEEN_SUBJECT)) {
handle_subject(line+9);
*seen |= SEEN_SUBJECT;
return;
}
}
if (!memcmp("[PATCH]", line, 7) && isspace(line[7])) {
if (!(*seen & SEEN_SUBJECT)) {
handle_subject(line);
*seen |= SEEN_SUBJECT;
return;
}
}
*seen |= SEEN_PREFIX;
}
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;
}
}
}
}
static void decode_header_bq(char *it);
typedef int (*header_fn_t)(char *);
struct header_def {
const char *name;
header_fn_t func;
int namelen;
};
static void check_header(char *line, 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])) {
/* Unwrap inline B and Q encoding, and optionally
* normalize the meta information to utf8.
*/
decode_header_bq(line + len + 2);
header[i].func(line + len + 2);
break;
}
}
}
static void check_subheader_line(char *line)
{
static struct header_def header[] = {
{ "Content-Type", handle_subcontent_type },
{ "Content-Transfer-Encoding",
handle_content_transfer_encoding },
{ NULL },
};
check_header(line, header);
}
static void check_header_line(char *line)
{
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, header);
}
static int is_rfc2822_header(char *line)
{
/*
* The section that defines the loosest possible
* field name is "3.6.8 Optional fields".
*
* optional-field = field-name ":" unstructured CRLF
* field-name = 1*ftext
* ftext = %d33-57 / %59-126
*/
int ch;
char *cp = line;
while ((ch = *cp++)) {
if (ch == ':')
return cp != line;
if ((33 <= ch && ch <= 57) ||
(59 <= ch && ch <= 126))
continue;
break;
}
return 0;
}
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)
break;
len = eatspace(line + ofs);
if (len == 0)
break;
if (!is_rfc2822_header(line)) {
/* Re-add the newline */
line[ofs + len] = '\n';
line[ofs + len + 1] = '\0';
break;
}
ofs += len;
/* Yuck, 2822 header "folding" */
peek = fgetc(in); ungetc(peek, in);
if (peek != ' ' && peek != '\t')
break;
}
/* Count mbox From headers as headers */
if (!ofs && !memcmp(line, "From ", 5))
ofs = 1;
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 rfc2047)
{
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++));
continue;
}
if (rfc2047 && c == '_') /* rfc2047 4.2 (2) */
c = 0x20;
*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)
{
#ifndef NO_ICONV
char *in, *out;
size_t insize, outsize, nrc;
char outbuf[4096]; /* cheat */
static char latin_one[] = "latin1";
char *input_charset = *charset ? charset : latin_one;
iconv_t conv = iconv_open(metainfo_charset, input_charset);
if (conv == (iconv_t) -1) {
static int warned_latin1_once = 0;
if (input_charset != latin_one) {
fprintf(stderr, "cannot convert from %s to %s\n",
input_charset, metainfo_charset);
*charset = 0;
}
else if (!warned_latin1_once) {
warned_latin1_once = 1;
fprintf(stderr, "tried to convert from %s to %s, "
"but your iconv does not work with it.\n",
input_charset, metainfo_charset);
}
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);
#endif
}
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, 1);
break;
}
if (sz < 0)
return;
if (metainfo_charset)
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, 0);
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;
sub = cleanup_subject(subject);
cleanup_space(name);
cleanup_space(date);
cleanup_space(email);
cleanup_space(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(int *seen)
{
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_charset)
convert_to_utf8(line, charset);
handle_inbody_header(seen, line);
if (!(*seen & SEEN_PREFIX))
continue;
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(int *seen)
{
int n = 0;
while (fgets(line, sizeof(line), stdin) != NULL) {
again:
n++;
if (is_multipart_boundary(line))
break;
if (handle_commit_msg(seen))
goto again;
handle_patch();
break;
}
if (n == 0)
return -1;
return 0;
}
static void handle_multipart_body(void)
{
int seen = 0;
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 hdr = read_one_header_line(line, sizeof(line), stdin);
if (!hdr) {
if (handle_multipart_one_part(&seen) < 0)
return;
/* Reset per part headers */
transfer_encoding = TE_DONTCARE;
charset[0] = 0;
}
else
check_subheader_line(line);
}
fclose(patchfile);
if (!patch_lines) {
fprintf(stderr, "No patch found\n");
exit(1);
}
}
/* Non multipart message */
static void handle_body(void)
{
int seen = 0;
if (line[0] || fgets(line, sizeof(line), stdin) != NULL) {
handle_commit_msg(&seen);
handle_patch();
}
fclose(patchfile);
if (!patch_lines) {
fprintf(stderr, "No patch found\n");
exit(1);
}
}
static const char mailinfo_usage[] =
"git-mailinfo [-k] [-u | --encoding=<encoding>] msg patch <mail >info";
int main(int argc, char **argv)
{
/* NEEDSWORK: might want to do the optional .git/ directory
* discovery
*/
git_config(git_default_config);
while (1 < argc && argv[1][0] == '-') {
if (!strcmp(argv[1], "-k"))
keep_subject = 1;
else if (!strcmp(argv[1], "-u"))
metainfo_charset = git_commit_encoding;
else if (!strncmp(argv[1], "--encoding=", 11))
metainfo_charset = argv[1] + 11;
else
usage(mailinfo_usage);
argc--; argv++;
}
if (argc != 3)
usage(mailinfo_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 hdr = read_one_header_line(line, sizeof(line), stdin);
if (!hdr) {
if (multipart_boundary[0])
handle_multipart_body();
else
handle_body();
handle_info();
break;
}
check_header_line(line);
}
return 0;
}