Add map_user() and clear_mailmap() to mailmap

map_user() allows to lookup and replace both email and
name of a user, based on a new style mailmap file.

The possible mailmap definitions are now:

  proper_name <commit_email>                             # Old style
  <proper_email> <commit_email>                          # New style
  proper_name <proper_email> <commit_email>              # New style
  proper_name <proper_email> commit_name <commit_email>  # New style

map_email() operates the same as before, with the
exception that it also will to try to match on a name
passed in through the name return buffer.

clear_mailmap() is needed to now clear the more complex
mailmap structure.

Signed-off-by: Marius Storm-Olsen <marius@trolltech.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

3 files changed, 236 insertions, 51 deletions

diff --git a/Documentation/git-shortlog.txt b/Documentation/git-shortlog.txt
index 66b604584..a0eaab525 100644
--- a/Documentation/git-shortlog.txt
+++ b/Documentation/git-shortlog.txt
@@ -48,24 +48,38 @@ OPTIONS
 FILES
 -----
 
-If a file `.mailmap` exists at the toplevel of the repository, or at the
-location pointed to by the log.mailmap configuration option,
-it is used to map an author email address to a canonical real name. This
-can be used to coalesce together commits by the same person where their
-name was spelled differently (whether with the same email address or
-not).
-
-Each line in the file consists, in this order, of the canonical real name
-of an author, whitespace, and an email address (enclosed by '<' and '>')
-to map to the name. Use hash '#' for comments, either on their own line,
-or after the email address.
-
-A canonical name may appear in more than one line, associated with
-different email addresses, but it doesn't make sense for a given address
-to appear more than once (if that happens, a later line overrides the
-earlier ones).
-
-So, for example, if your history contains commits by two authors, Jane
+If the file `.mailmap` exists at the toplevel of the repository, or at
+the location pointed to by the mailmap.file configuration option, it
+is used to map author and committer names and email addresses to
+canonical real names and email addresses.
+This mapping can be used to coalesce together commits by the same
+person where their name and/or email address was spelled differently.
+
+In the simple form, each line in the file consists of the canonical
+real name of an author, whitespace, and an email address used in the
+commit (enclosed by '<' and '>') to map to the name. Thus, looks like
+this
+--
+	Proper Name <commit@email.xx>
+--
+
+The more complex forms are
+--
+	<proper@email.xx> <commit@email.xx>
+--
+which allows mailmap to replace only the email part of a commit, and
+--
+	Proper Name <proper@email.xx> <commit@email.xx>
+--
+which allows mailmap to replace both the name and the email of a
+commit matching the specified commit email address, and
+--
+	Proper Name <proper@email.xx> Commit Name <commit@email.xx>
+--
+which allows mailmap to replace both the name and the email of a
+commit matching both the specified commit name and email address.
+
+Example 1: Your history contains commits by two authors, Jane
 and Joe, whose names appear in the repository under several forms:
 
 ------------
@@ -76,16 +90,43 @@ Jane Doe <jane@laptop.(none)>
 Jane D. <jane@desktop.(none)>
 ------------
 
-Then, supposing Joe wants his middle name initial used, and Jane prefers
-her family name fully spelled out, a proper `.mailmap` file would look like:
+Now suppose that Joe wants his middle name initial used, and Jane
+prefers her family name fully spelled out. A proper `.mailmap` file
+would look like:
 
 ------------
-# Note how we don't need an entry for <jane@laptop.(none)>, because the
-# real name of that author is correct already, and coalesced directly.
-Jane Doe <jane@desktop.(none)>
+Jane Doe         <jane@desktop.(none)>
 Joe R. Developer <joe@example.com>
 ------------
 
+Note how we don't need an entry for <jane@laptop.(none)>, because the
+real name of that author is correct already, and coalesced directly.
+
+Example 2: Your repository contains commits from the following
+authors:
+
+------------
+nick1 <bugs@company.xx>
+nick2 <bugs@company.xx>
+nick2 <nick2@company.xx>
+santa <me@company.xx>
+claus <me@company.xx>
+CTO <cto@coompany.xx>
+------------
+
+Then, you might want a `.mailmap` file looking like:
+------------
+<cto@company.xx>                       <cto@coompany.xx>
+Some Dude <some@dude.xx>         nick1 <bugs@company.xx>
+Other Author <other@author.xx>   nick2 <bugs@company.xx>
+Other Author <other@author.xx>         <nick2@company.xx>
+Santa Claus <santa.claus@northpole.xx> <me@company.xx>
+------------
+
+Use hash '#' for comments that are either on their own line, or after
+the email address.
+
+
 Author
 ------
 Written by Jeff Garzik <jgarzik@pobox.com>
diff --git a/mailmap.c b/mailmap.c
index d006dad67..f12bb45a3 100644
--- a/mailmap.c
+++ b/mailmap.c
@@ -2,7 +2,122 @@
 #include "string-list.h"
 #include "mailmap.h"
 
+#define DEBUG_MAILMAP 0
+#if DEBUG_MAILMAP
+#define debug_mm(...) fprintf(stderr, __VA_ARGS__)
+#else
+static inline void debug_mm(const char *format, ...) {}
+#endif
+
 const char *git_mailmap_file;
+
+struct mailmap_info {
+	char *name;
+	char *email;
+};
+
+struct mailmap_entry {
+	/* name and email for the simple mail-only case */
+	char *name;
+	char *email;
+
+	/* name and email for the complex mail and name matching case */
+	struct string_list namemap;
+};
+
+static void free_mailmap_info(void *p, const char *s)
+{
+	struct mailmap_info *mi = (struct mailmap_info *)p;
+	debug_mm("mailmap: -- complex: '%s' -> '%s' <%s>\n", s, mi->name, mi->email);
+	free(mi->name);
+	free(mi->email);
+}
+
+static void free_mailmap_entry(void *p, const char *s)
+{
+	struct mailmap_entry *me = (struct mailmap_entry *)p;
+	debug_mm("mailmap: removing entries for <%s>, with %d sub-entries\n", s, me->namemap.nr);
+	debug_mm("mailmap: - simple: '%s' <%s>\n", me->name, me->email);
+	free(me->name);
+	free(me->email);
+
+	me->namemap.strdup_strings = 1;
+	string_list_clear_func(&me->namemap, free_mailmap_info);
+}
+
+static void add_mapping(struct string_list *map,
+			char *new_name, char *new_email, char *old_name, char *old_email)
+{
+	struct mailmap_entry *me;
+	int index;
+	if (old_email == NULL) {
+		old_email = new_email;
+		new_email = NULL;
+	}
+
+	if ((index = string_list_find_insert_index(map, old_email, 1)) < 0) {
+		/* mailmap entry exists, invert index value */
+		index = -1 - index;
+	} else {
+		/* create mailmap entry */
+		struct string_list_item *item = string_list_insert_at_index(index, old_email, map);
+		item->util = xmalloc(sizeof(struct mailmap_entry));
+		memset(item->util, 0, sizeof(struct mailmap_entry));
+		((struct mailmap_entry *)item->util)->namemap.strdup_strings = 1;
+	}
+	me = (struct mailmap_entry *)map->items[index].util;
+
+	if (old_name == NULL) {
+		debug_mm("mailmap: adding (simple) entry for %s at index %d\n", old_email, index);
+		/* Replace current name and new email for simple entry */
+		free(me->name);
+		free(me->email);
+		if (new_name)
+			me->name = xstrdup(new_name);
+		if (new_email)
+			me->email = xstrdup(new_email);
+	} else {
+		struct mailmap_info *mi = xmalloc(sizeof(struct mailmap_info));
+		debug_mm("mailmap: adding (complex) entry for %s at index %d\n", old_email, index);
+		if (new_name)
+			mi->name = xstrdup(new_name);
+		if (new_email)
+			mi->email = xstrdup(new_email);
+		string_list_insert(old_name, &me->namemap)->util = mi;
+	}
+
+	debug_mm("mailmap:  '%s' <%s> -> '%s' <%s>\n",
+		 old_name, old_email, new_name, new_email);
+}
+
+static char *parse_name_and_email(char *buffer, char **name, char **email)
+{
+	char *left, *right, *nstart, *nend;
+	*name = *email = 0;
+
+	if ((left = strchr(buffer, '<')) == NULL)
+		return NULL;
+	if ((right = strchr(left+1, '>')) == NULL)
+		return NULL;
+	if (left+1 == right)
+		return NULL;
+
+	/* remove whitespace from beginning and end of name */
+	nstart = buffer;
+	while (isspace(*nstart) && nstart < left)
+		++nstart;
+	nend = left-1;
+	while (isspace(*nend) && nend > nstart)
+		--nend;
+
+	*name = (nstart < nend ? nstart : NULL);
+	*email = left+1;
+	*(nend+1) = '\0';
+	*right++ = '\0';
+
+	return (*right == '\0' ? NULL : right);
+}
+
 static int read_single_mailmap(struct string_list *map, const char *filename, char **repo_abbrev)
 {
 	char buffer[1024];
@@ -11,9 +126,7 @@ static int read_single_mailmap(struct string_list *map, const char *filename, ch
 	if (f == NULL)
 		return 1;
 	while (fgets(buffer, sizeof(buffer), f) != NULL) {
-		char *end_of_name, *left_bracket, *right_bracket;
-		char *name, *email;
-		int i;
+		char *name1 = 0, *email1 = 0, *name2 = 0, *email2 = 0;
 		if (buffer[0] == '#') {
 			static const char abbrev[] = "# repo-abbrev:";
 			int abblen = sizeof(abbrev) - 1;
@@ -37,25 +150,11 @@ static int read_single_mailmap(struct string_list *map, const char *filename, ch
 			}
 			continue;
 		}
-		if ((left_bracket = strchr(buffer, '<')) == NULL)
-			continue;
-		if ((right_bracket = strchr(left_bracket + 1, '>')) == NULL)
-			continue;
-		if (right_bracket == left_bracket + 1)
-			continue;
-		for (end_of_name = left_bracket;
-		     end_of_name != buffer && isspace(end_of_name[-1]);
-		     end_of_name--)
-			; /* keep on looking */
-		if (end_of_name == buffer)
-			continue;
-		name = xmalloc(end_of_name - buffer + 1);
-		strlcpy(name, buffer, end_of_name - buffer + 1);
-		email = xmalloc(right_bracket - left_bracket);
-		for (i = 0; i < right_bracket - left_bracket - 1; i++)
-			email[i] = tolower(left_bracket[i + 1]);
-		email[right_bracket - left_bracket - 1] = '\0';
-		string_list_insert(email, map)->util = name;
+		if ((name2 = parse_name_and_email(buffer, &name1, &email1)) != NULL)
+			parse_name_and_email(name2, &name2, &email2);
+
+		if (email1)
+			add_mapping(map, name1, email1, name2, email2);
 	}
 	fclose(f);
 	return 0;
@@ -63,22 +162,37 @@ static int read_single_mailmap(struct string_list *map, const char *filename, ch
 
 int read_mailmap(struct string_list *map, char **repo_abbrev)
 {
+	map->strdup_strings = 1;
 	/* each failure returns 1, so >1 means both calls failed */
 	return read_single_mailmap(map, ".mailmap", repo_abbrev) +
 	       read_single_mailmap(map, git_mailmap_file, repo_abbrev) > 1;
 }
 
-int map_email(struct string_list *map, const char *email, char *name, int maxlen)
+void clear_mailmap(struct string_list *map)
+{
+	debug_mm("mailmap: clearing %d entries...\n", map->nr);
+	map->strdup_strings = 1;
+	string_list_clear_func(map, free_mailmap_entry);
+	debug_mm("mailmap: cleared\n");
+}
+
+int map_user(struct string_list *map,
+	     char *email, int maxlen_email, char *name, int maxlen_name)
 {
 	char *p;
 	struct string_list_item *item;
+	struct mailmap_entry *me;
 	char buf[1024], *mailbuf;
 	int i;
 
-	/* autocomplete common developers */
+	/* figure out space requirement for email */
 	p = strchr(email, '>');
-	if (!p)
-		return 0;
+	if (!p) {
+		/* email passed in might not be wrapped in <>, but end with a \0 */
+		p = memchr(email, '\0', maxlen_email);
+		if (p == 0)
+			return 0;
+	}
 	if (p - email + 1 < sizeof(buf))
 		mailbuf = buf;
 	else
@@ -88,13 +202,39 @@ int map_email(struct string_list *map, const char *email, char *name, int maxlen
 	for (i = 0; i < p - email; i++)
 		mailbuf[i] = tolower(email[i]);
 	mailbuf[i] = 0;
+
+	debug_mm("map_user: map '%s' <%s>\n", name, mailbuf);
 	item = string_list_lookup(mailbuf, map);
+	if (item != NULL) {
+		me = (struct mailmap_entry *)item->util;
+		if (me->namemap.nr) {
+			/* The item has multiple items, so we'll look up on name too */
+			/* If the name is not found, we choose the simple entry      */
+			struct string_list_item *subitem = string_list_lookup(name, &me->namemap);
+			if (subitem)
+				item = subitem;
+		}
+	}
 	if (mailbuf != buf)
 		free(mailbuf);
 	if (item != NULL) {
-		const char *realname = (const char *)item->util;
-		strlcpy(name, realname, maxlen);
+		struct mailmap_info *mi = (struct mailmap_info *)item->util;
+		if (mi->name == NULL && (mi->email == NULL || maxlen_email == 0)) {
+			debug_mm("map_user:  -- (no simple mapping)\n");
+			return 0;
+		}
+		if (maxlen_email && mi->email)
+			strlcpy(email, mi->email, maxlen_email);
+		if (maxlen_name && mi->name)
+			strlcpy(name, mi->name, maxlen_name);
+		debug_mm("map_user:  to '%s' <%s>\n", name, mi->email ? mi->email : "");
 		return 1;
 	}
+	debug_mm("map_user:  --\n");
 	return 0;
 }
+
+int map_email(struct string_list *map, const char *email, char *name, int maxlen)
+{
+	return map_user(map, (char *)email, 0, name, maxlen);
+}
diff --git a/mailmap.h b/mailmap.h
index ba2ee7670..4b2ca3a7d 100644
--- a/mailmap.h
+++ b/mailmap.h
@@ -2,6 +2,10 @@
 #define MAILMAP_H
 
 int read_mailmap(struct string_list *map, char **repo_abbrev);
+void clear_mailmap(struct string_list *map);
+
 int map_email(struct string_list *mailmap, const char *email, char *name, int maxlen);
+int map_user(struct string_list *mailmap,
+	     char *email, int maxlen_email, char *name, int maxlen_name);
 
 #endif