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-rw-r--r--builtin-mailinfo.c947
1 files changed, 947 insertions, 0 deletions
diff --git a/builtin-mailinfo.c b/builtin-mailinfo.c
new file mode 100644
index 0000000..b4f6e91
--- /dev/null
+++ b/builtin-mailinfo.c
@@ -0,0 +1,947 @@
+/*
+ * Another stupid program, this one parsing the headers of an
+ * email to figure out authorship and subject
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "utf8.h"
+
+static FILE *cmitmsg, *patchfile, *fin, *fout;
+
+static int keep_subject;
+static const char *metainfo_charset;
+static char line[1000];
+static char name[1000];
+static char email[1000];
+
+static enum {
+ TE_DONTCARE, TE_QP, TE_BASE64,
+} transfer_encoding;
+static enum {
+ TYPE_TEXT, TYPE_OTHER,
+} message_type;
+
+static char charset[256];
+static int patch_lines;
+static char **p_hdr_data, **s_hdr_data;
+
+#define MAX_HDR_PARSED 10
+#define MAX_BOUNDARIES 5
+
+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_header(char *line, char *data, int ofs)
+{
+ if (!line || !data)
+ return 1;
+
+ strcpy(data, line+ofs);
+
+ 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)
+{
+ const 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;
+}
+
+struct content_type {
+ char *boundary;
+ int boundary_len;
+};
+
+static struct content_type content[MAX_BOUNDARIES];
+
+static struct content_type *content_top = content;
+
+static int handle_content_type(char *line)
+{
+ char boundary[256];
+
+ if (strcasestr(line, "text/") == NULL)
+ message_type = TYPE_OTHER;
+ if (slurp_attr(line, "boundary=", boundary + 2)) {
+ memcpy(boundary, "--", 2);
+ if (content_top++ >= &content[MAX_BOUNDARIES]) {
+ fprintf(stderr, "Too many boundaries to handle\n");
+ exit(1);
+ }
+ content_top->boundary_len = strlen(boundary);
+ content_top->boundary = xmalloc(content_top->boundary_len+1);
+ strcpy(content_top->boundary, boundary);
+ }
+ if (slurp_attr(line, "charset=", charset)) {
+ int i, c;
+ for (i = 0; (c = charset[i]) != 0; i++)
+ charset[i] = tolower(c);
+ }
+ 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, content_top->boundary, content_top->boundary_len));
+}
+
+static int eatspace(char *line)
+{
+ int len = strlen(line);
+ while (len > 0 && isspace(line[len-1]))
+ line[--len] = 0;
+ return len;
+}
+
+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;
+ }
+ eatspace(subject);
+ 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(char *it);
+static char *header[MAX_HDR_PARSED] = {
+ "From","Subject","Date",
+};
+
+static int check_header(char *line, char **hdr_data, int overwrite)
+{
+ int i;
+
+ /* search for the interesting parts */
+ for (i = 0; header[i]; i++) {
+ int len = strlen(header[i]);
+ if ((!hdr_data[i] || overwrite) &&
+ !strncasecmp(line, header[i], len) &&
+ line[len] == ':' && isspace(line[len + 1])) {
+ /* Unwrap inline B and Q encoding, and optionally
+ * normalize the meta information to utf8.
+ */
+ decode_header(line + len + 2);
+ hdr_data[i] = xmalloc(1000 * sizeof(char));
+ if (! handle_header(line, hdr_data[i], len + 2)) {
+ return 1;
+ }
+ }
+ }
+
+ /* Content stuff */
+ if (!strncasecmp(line, "Content-Type", 12) &&
+ line[12] == ':' && isspace(line[12 + 1])) {
+ decode_header(line + 12 + 2);
+ if (! handle_content_type(line)) {
+ return 1;
+ }
+ }
+ if (!strncasecmp(line, "Content-Transfer-Encoding", 25) &&
+ line[25] == ':' && isspace(line[25 + 1])) {
+ decode_header(line + 25 + 2);
+ if (! handle_content_transfer_encoding(line)) {
+ return 1;
+ }
+ }
+
+ /* for inbody stuff */
+ if (!memcmp(">From", line, 5) && isspace(line[5]))
+ return 1;
+ if (!memcmp("[PATCH]", line, 7) && isspace(line[7])) {
+ for (i = 0; header[i]; i++) {
+ if (!memcmp("Subject: ", header[i], 9)) {
+ if (! handle_header(line, hdr_data[i], 0)) {
+ return 1;
+ }
+ }
+ }
+ }
+
+ /* no match */
+ return 0;
+}
+
+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;
+
+ /* Count mbox From headers as headers */
+ if (!memcmp(line, "From ", 5) || !memcmp(line, ">From ", 6))
+ return 1;
+
+ while ((ch = *cp++)) {
+ if (ch == ':')
+ return cp != line;
+ if ((33 <= ch && ch <= 57) ||
+ (59 <= ch && ch <= 126))
+ continue;
+ break;
+ }
+ return 0;
+}
+
+/*
+ * sz is size of 'line' buffer in bytes. Must be reasonably
+ * long enough to hold one physical real-world e-mail line.
+ */
+static int read_one_header_line(char *line, int sz, FILE *in)
+{
+ int len;
+
+ /*
+ * We will read at most (sz-1) bytes and then potentially
+ * re-add NUL after it. Accessing line[sz] after this is safe
+ * and we can allow len to grow up to and including sz.
+ */
+ sz--;
+
+ /* Get the first part of the line. */
+ if (!fgets(line, sz, in))
+ return 0;
+
+ /*
+ * Is it an empty line or not a valid rfc2822 header?
+ * If so, stop here, and return false ("not a header")
+ */
+ len = eatspace(line);
+ if (!len || !is_rfc2822_header(line)) {
+ /* Re-add the newline */
+ line[len] = '\n';
+ line[len + 1] = '\0';
+ return 0;
+ }
+
+ /*
+ * Now we need to eat all the continuation lines..
+ * Yuck, 2822 header "folding"
+ */
+ for (;;) {
+ int peek, addlen;
+ static char continuation[1000];
+
+ peek = fgetc(in); ungetc(peek, in);
+ if (peek != ' ' && peek != '\t')
+ break;
+ if (!fgets(continuation, sizeof(continuation), in))
+ break;
+ addlen = eatspace(continuation);
+ if (len < sz - 1) {
+ if (addlen >= sz - len)
+ addlen = sz - len - 1;
+ memcpy(line + len, continuation, addlen);
+ len += addlen;
+ }
+ }
+ line[len] = 0;
+
+ return 1;
+}
+
+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;
+}
+
+/*
+ * When there is no known charset, guess.
+ *
+ * Right now we assume that if the target is UTF-8 (the default),
+ * and it already looks like UTF-8 (which includes US-ASCII as its
+ * subset, of course) then that is what it is and there is nothing
+ * to do.
+ *
+ * Otherwise, we default to assuming it is Latin1 for historical
+ * reasons.
+ */
+static const char *guess_charset(const char *line, const char *target_charset)
+{
+ if (is_encoding_utf8(target_charset)) {
+ if (is_utf8(line))
+ return NULL;
+ }
+ return "latin1";
+}
+
+static void convert_to_utf8(char *line, const char *charset)
+{
+ char *out;
+
+ if (!charset || !*charset) {
+ charset = guess_charset(line, metainfo_charset);
+ if (!charset)
+ return;
+ }
+
+ if (!strcmp(metainfo_charset, charset))
+ return;
+ out = reencode_string(line, metainfo_charset, charset);
+ if (!out)
+ die("cannot convert from %s to %s\n",
+ charset, metainfo_charset);
+ strcpy(line, out);
+ free(out);
+}
+
+static int decode_header_bq(char *it)
+{
+ char *in, *out, *ep, *cp, *sp;
+ char outbuf[1000];
+ int rfc2047 = 0;
+
+ in = it;
+ out = outbuf;
+ while ((ep = strstr(in, "=?")) != NULL) {
+ int sz, encoding;
+ char charset_q[256], piecebuf[256];
+ rfc2047 = 1;
+
+ 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 rfc2047; /* 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 rfc2047; /* no munging */
+ ep = strstr(cp + 3, "?=");
+ if (!ep)
+ return rfc2047; /* no munging */
+ switch (tolower(encoding)) {
+ default:
+ return rfc2047; /* 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 rfc2047;
+ if (metainfo_charset)
+ convert_to_utf8(piecebuf, charset_q);
+ strcpy(out, piecebuf);
+ out += strlen(out);
+ in = ep + 2;
+ }
+ strcpy(out, in);
+ strcpy(it, outbuf);
+ return rfc2047;
+}
+
+static void decode_header(char *it)
+{
+
+ if (decode_header_bq(it))
+ return;
+ /* otherwise "it" is a straight copy of the input.
+ * This can be binary guck but there is no charset specified.
+ */
+ if (metainfo_charset)
+ convert_to_utf8(it, "");
+}
+
+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 int handle_filter(char *line);
+
+static int find_boundary(void)
+{
+ while(fgets(line, sizeof(line), fin) != NULL) {
+ if (is_multipart_boundary(line))
+ return 1;
+ }
+ return 0;
+}
+
+static int handle_boundary(void)
+{
+ char newline[]="\n";
+again:
+ if (!memcmp(line+content_top->boundary_len, "--", 2)) {
+ /* we hit an end boundary */
+ /* pop the current boundary off the stack */
+ free(content_top->boundary);
+
+ /* technically won't happen as is_multipart_boundary()
+ will fail first. But just in case..
+ */
+ if (content_top-- < content) {
+ fprintf(stderr, "Detected mismatched boundaries, "
+ "can't recover\n");
+ exit(1);
+ }
+ handle_filter(newline);
+
+ /* skip to the next boundary */
+ if (!find_boundary())
+ return 0;
+ goto again;
+ }
+
+ /* set some defaults */
+ transfer_encoding = TE_DONTCARE;
+ charset[0] = 0;
+ message_type = TYPE_TEXT;
+
+ /* slurp in this section's info */
+ while (read_one_header_line(line, sizeof(line), fin))
+ check_header(line, p_hdr_data, 0);
+
+ /* eat the blank line after section info */
+ return (fgets(line, sizeof(line), fin) != NULL);
+}
+
+static inline int patchbreak(const char *line)
+{
+ /* Beginning of a "diff -" header? */
+ if (!memcmp("diff -", line, 6))
+ return 1;
+
+ /* CVS "Index: " line? */
+ if (!memcmp("Index: ", line, 7))
+ return 1;
+
+ /*
+ * "--- <filename>" starts patches without headers
+ * "---<sp>*" is a manual separator
+ */
+ if (!memcmp("---", line, 3)) {
+ line += 3;
+ /* space followed by a filename? */
+ if (line[0] == ' ' && !isspace(line[1]))
+ return 1;
+ /* Just whitespace? */
+ for (;;) {
+ unsigned char c = *line++;
+ if (c == '\n')
+ return 1;
+ if (!isspace(c))
+ break;
+ }
+ return 0;
+ }
+ return 0;
+}
+
+
+static int handle_commit_msg(char *line)
+{
+ static int still_looking = 1;
+
+ if (!cmitmsg)
+ return 0;
+
+ if (still_looking) {
+ char *cp = line;
+ if (isspace(*line)) {
+ for (cp = line + 1; *cp; cp++) {
+ if (!isspace(*cp))
+ break;
+ }
+ if (!*cp)
+ return 0;
+ }
+ if ((still_looking = check_header(cp, s_hdr_data, 0)) != 0)
+ return 0;
+ }
+
+ /* normalize the log message to UTF-8. */
+ if (metainfo_charset)
+ convert_to_utf8(line, charset);
+
+ if (patchbreak(line)) {
+ fclose(cmitmsg);
+ cmitmsg = NULL;
+ return 1;
+ }
+
+ fputs(line, cmitmsg);
+ return 0;
+}
+
+static int handle_patch(char *line)
+{
+ fputs(line, patchfile);
+ patch_lines++;
+ return 0;
+}
+
+static int handle_filter(char *line)
+{
+ static int filter = 0;
+
+ /* filter tells us which part we left off on
+ * a non-zero return indicates we hit a filter point
+ */
+ switch (filter) {
+ case 0:
+ if (!handle_commit_msg(line))
+ break;
+ filter++;
+ case 1:
+ if (!handle_patch(line))
+ break;
+ filter++;
+ default:
+ return 1;
+ }
+
+ return 0;
+}
+
+static void handle_body(void)
+{
+ int rc = 0;
+ static char newline[2000];
+ static char *np = newline;
+
+ /* Skip up to the first boundary */
+ if (content_top->boundary) {
+ if (!find_boundary())
+ return;
+ }
+
+ do {
+ /* process any boundary lines */
+ if (content_top->boundary && is_multipart_boundary(line)) {
+ /* flush any leftover */
+ if ((transfer_encoding == TE_BASE64) &&
+ (np != newline)) {
+ handle_filter(newline);
+ }
+ if (!handle_boundary())
+ return;
+ }
+
+ /* Unwrap transfer encoding */
+ decode_transfer_encoding(line);
+
+ switch (transfer_encoding) {
+ case TE_BASE64:
+ {
+ char *op = line;
+
+ /* binary data most likely doesn't have newlines */
+ if (message_type != TYPE_TEXT) {
+ rc = handle_filter(line);
+ break;
+ }
+
+ /* this is a decoded line that may contain
+ * multiple new lines. Pass only one chunk
+ * at a time to handle_filter()
+ */
+
+ do {
+ while (*op != '\n' && *op != 0)
+ *np++ = *op++;
+ *np = *op;
+ if (*np != 0) {
+ /* should be sitting on a new line */
+ *(++np) = 0;
+ op++;
+ rc = handle_filter(newline);
+ np = newline;
+ }
+ } while (*op != 0);
+ /* the partial chunk is saved in newline and
+ * will be appended by the next iteration of fgets
+ */
+ break;
+ }
+ default:
+ rc = handle_filter(line);
+ }
+ if (rc)
+ /* nothing left to filter */
+ break;
+ } while (fgets(line, sizeof(line), fin));
+
+ return;
+}
+
+static void handle_info(void)
+{
+ char *sub;
+ char *hdr;
+ int i;
+
+ for (i = 0; header[i]; i++) {
+
+ /* only print inbody headers if we output a patch file */
+ if (patch_lines && s_hdr_data[i])
+ hdr = s_hdr_data[i];
+ else if (p_hdr_data[i])
+ hdr = p_hdr_data[i];
+ else
+ continue;
+
+ if (!memcmp(header[i], "Subject", 7)) {
+ sub = cleanup_subject(hdr);
+ cleanup_space(sub);
+ fprintf(fout, "Subject: %s\n", sub);
+ } else if (!memcmp(header[i], "From", 4)) {
+ handle_from(hdr);
+ fprintf(fout, "Author: %s\n", name);
+ fprintf(fout, "Email: %s\n", email);
+ } else {
+ cleanup_space(hdr);
+ fprintf(fout, "%s: %s\n", header[i], hdr);
+ }
+ }
+ fprintf(fout, "\n");
+}
+
+static int mailinfo(FILE *in, FILE *out, int ks, const char *encoding,
+ const char *msg, const char *patch)
+{
+ keep_subject = ks;
+ metainfo_charset = encoding;
+ fin = in;
+ fout = out;
+
+ cmitmsg = fopen(msg, "w");
+ if (!cmitmsg) {
+ perror(msg);
+ return -1;
+ }
+ patchfile = fopen(patch, "w");
+ if (!patchfile) {
+ perror(patch);
+ fclose(cmitmsg);
+ return -1;
+ }
+
+ p_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(char *));
+ s_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(char *));
+
+ /* process the email header */
+ while (read_one_header_line(line, sizeof(line), fin))
+ check_header(line, p_hdr_data, 1);
+
+ handle_body();
+ handle_info();
+
+ return 0;
+}
+
+static const char mailinfo_usage[] =
+ "git-mailinfo [-k] [-u | --encoding=<encoding>] msg patch <mail >info";
+
+int cmd_mailinfo(int argc, const char **argv, const char *prefix)
+{
+ const char *def_charset;
+
+ /* NEEDSWORK: might want to do the optional .git/ directory
+ * discovery
+ */
+ git_config(git_default_config);
+
+ def_charset = (git_commit_encoding ? git_commit_encoding : "utf-8");
+ metainfo_charset = def_charset;
+
+ while (1 < argc && argv[1][0] == '-') {
+ if (!strcmp(argv[1], "-k"))
+ keep_subject = 1;
+ else if (!strcmp(argv[1], "-u"))
+ metainfo_charset = def_charset;
+ else if (!strcmp(argv[1], "-n"))
+ metainfo_charset = NULL;
+ else if (!prefixcmp(argv[1], "--encoding="))
+ metainfo_charset = argv[1] + 11;
+ else
+ usage(mailinfo_usage);
+ argc--; argv++;
+ }
+
+ if (argc != 3)
+ usage(mailinfo_usage);
+
+ return !!mailinfo(stdin, stdout, keep_subject, metainfo_charset, argv[1], argv[2]);
+}