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-rw-r--r--mailinfo.c749
1 files changed, 749 insertions, 0 deletions
diff --git a/mailinfo.c b/mailinfo.c
new file mode 100644
index 000000000..df470bb9c
--- /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;
+}