libbb: password/group function helpers rewritten by Tito:

function                                             old     new   delta
xgetpwuid                                              -      27     +27
uid2uname_utoa                                         -      22     +22
gid2group_utoa                                         -      22     +22
uid2uname                                              -      18     +18
gid2group                                              -      18     +18
buffer_fill_and_print                                179     196     +17
print_user                                            12      24     +12
print_group                                           12      24     +12
get_cached                                            89      99     +10
...
print_common                                         134     120     -14
vlock_main                                           415     396     -19
logger_main                                          410     387     -23
crontab_main                                         642     609     -33
bb_getpwuid                                           42       -     -42
bb_getgrgid                                           42       -     -42
bb_getug                                              80       -     -80
------------------------------------------------------------------------------
(add/remove: 6/3 grow/shrink: 9/11 up/down: 187/-296)        Total: -109 bytes

11 files changed, 84 insertions, 94 deletions

diff --git a/coreutils/id.c b/coreutils/id.c
index 6ddb236..33e06f4 100644
--- a/coreutils/id.c
+++ b/coreutils/id.c
@@ -36,12 +36,8 @@ enum {
 #endif
 };
 
-static int print_common(unsigned id,
-		char* FAST_FUNC bb_getXXXid(char *name, int bufsize, long uid),
-		const char *prefix)
+static int print_common(unsigned id, const char *name, const char *prefix)
 {
-	const char *name = bb_getXXXid(NULL, 0, id);
-
 	if (prefix) {
 		printf("%s", prefix);
 	}
@@ -65,12 +61,12 @@ static int print_common(unsigned id,
 
 static int print_group(gid_t id, const char *prefix)
 {
-	return print_common(id, bb_getgrgid, prefix);
+	return print_common(id, gid2group(id), prefix);
 }
 
 static int print_user(uid_t id, const char *prefix)
 {
-	return print_common(id, bb_getpwuid, prefix);
+	return print_common(id, uid2uname(id), prefix);
 }
 
 /* On error set *n < 0 and return >= 0
diff --git a/coreutils/whoami.c b/coreutils/whoami.c
index 6756d4b..0dbcba9 100644
--- a/coreutils/whoami.c
+++ b/coreutils/whoami.c
@@ -20,7 +20,7 @@ int whoami_main(int argc, char **argv UNUSED_PARAM)
 		bb_show_usage();
 
 	/* Will complain and die if username not found */
-	puts(bb_getpwuid(NULL, -1, geteuid()));
+	puts(xuid2uname(geteuid()));
 
 	return fflush(stdout);
 }
diff --git a/include/libbb.h b/include/libbb.h
index e4ccc75..acae93a 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -702,14 +702,14 @@ int get_uidgid(struct bb_uidgid_t*, const char*, int numeric_ok) FAST_FUNC;
 void xget_uidgid(struct bb_uidgid_t*, const char*) FAST_FUNC;
 /* chown-like handling of "user[:[group]" */
 void parse_chown_usergroup_or_die(struct bb_uidgid_t *u, char *user_group) FAST_FUNC;
-/* bb_getpwuid, bb_getgrgid:
- * bb_getXXXid(buf, bufsz, id) - copy user/group name or id
- *              as a string to buf, return user/group name or NULL
- * bb_getXXXid(NULL, 0, id) - return user/group name or NULL
- * bb_getXXXid(NULL, -1, id) - return user/group name or exit
-*/
-char *bb_getpwuid(char *name, int bufsize, long uid) FAST_FUNC;
-char *bb_getgrgid(char *group, int bufsize, long gid) FAST_FUNC;
+struct passwd* xgetpwuid(uid_t uid) FAST_FUNC;
+struct group* xgetgrgid(gid_t gid) FAST_FUNC;
+char* xuid2uname(uid_t uid) FAST_FUNC;
+char* xgid2group(gid_t gid) FAST_FUNC;
+char* uid2uname(uid_t uid) FAST_FUNC;
+char* gid2group(gid_t gid) FAST_FUNC;
+char* uid2uname_utoa(long uid) FAST_FUNC;
+char* gid2group_utoa(long gid) FAST_FUNC;
 /* versions which cache results (useful for ps, ls etc) */
 const char* get_cached_username(uid_t uid) FAST_FUNC;
 const char* get_cached_groupname(gid_t gid) FAST_FUNC;
diff --git a/libbb/bb_pwd.c b/libbb/bb_pwd.c
index 65eb692..5e44edc 100644
--- a/libbb/bb_pwd.c
+++ b/libbb/bb_pwd.c
@@ -3,79 +3,72 @@
  * password utility routines.
  *
  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2008 by Tito Ragusa <farmatito@tiscali.it>
  *
  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  */
 
 #include "libbb.h"
 
-#define assert(x) ((void)0)
-
-/* internal function for bb_getpwuid and bb_getgrgid */
-/* Hacked by Tito Ragusa (c) 2004 <farmatito@tiscali.it> to make it more
- * flexible:
- *
- * bufsize > 0:      If idname is not NULL it is copied to buffer,
- *                   and buffer is returned. Else id as string is written
- *                   to buffer, and NULL is returned.
- *
- * bufsize == 0:     idname is returned.
- *
- * bufsize < 0:      If idname is not NULL it is returned.
- *                   Else an error message is printed and the program exits.
+/* TODO: maybe change API to return malloced data?
+ * This will allow to stop using libc functions returning
+ * pointers to static data (getpwuid)
  */
-static char* bb_getug(char *buffer, int bufsize, char *idname, long id, char prefix)
+
+/* TODO: add xgetpwnam, this construct is used a lot */
+
+struct passwd* FAST_FUNC xgetpwuid(uid_t uid)
 {
-	if (bufsize > 0) {
-		assert(buffer != NULL);
-		if (idname) {
-			return safe_strncpy(buffer, idname, bufsize);
-		}
-		snprintf(buffer, bufsize, "%ld", id);
-	} else if (bufsize < 0 && !idname) {
-		bb_error_msg_and_die("unknown %cid %ld", prefix, id);
-	}
-	return idname;
+	struct passwd *pw = getpwuid(uid);
+	if (!pw)
+		bb_error_msg_and_die("unknown uid %u", (unsigned)uid);
+	return pw;
 }
 
-/* bb_getpwuid, bb_getgrgid:
- * bb_getXXXid(buf, bufsz, id) - copy user/group name or id
- *               as a string to buf, return user/group name or NULL
- * bb_getXXXid(NULL, 0, id) - return user/group name or NULL
- * bb_getXXXid(NULL, -1, id) - return user/group name or exit
- */
-/* gets a username given a uid */
-char* FAST_FUNC bb_getpwuid(char *name, int bufsize, long uid)
+struct group* FAST_FUNC xgetgrgid(gid_t gid)
 {
-	struct passwd *myuser = getpwuid(uid);
+	struct group *gr = getgrgid(gid);
+	if (!gr)
+		bb_error_msg_and_die("unknown gid %u", (unsigned)gid);
+	return gr;
+}
 
-	return bb_getug(name, bufsize,
-			(myuser ? myuser->pw_name : (char*)myuser),
-			uid, 'u');
+char* FAST_FUNC xuid2uname(uid_t uid)
+{
+	struct passwd *pw = xgetpwuid(uid);
+	return pw->pw_name;
 }
-/* gets a groupname given a gid */
-char* FAST_FUNC bb_getgrgid(char *group, int bufsize, long gid)
+
+char* FAST_FUNC xgid2group(gid_t gid)
 {
-	struct group *mygroup = getgrgid(gid);
+	struct group *gr = xgetgrgid(gid);
+	return gr->gr_name;
+}
 
-	return bb_getug(group, bufsize,
-			(mygroup ? mygroup->gr_name : (char*)mygroup),
-			gid, 'g');
+char* FAST_FUNC uid2uname(uid_t uid)
+{
+	struct passwd *pw = getpwuid(uid);
+	return (pw) ? pw->pw_name : NULL;
 }
 
-/* returns a gid given a group name */
-long FAST_FUNC xgroup2gid(const char *name)
+char* FAST_FUNC gid2group(gid_t gid)
 {
-	struct group *mygroup;
+	struct group *gr = getgrgid(gid);
+	return (gr) ? gr->gr_name : NULL;
+}
 
-	mygroup = getgrnam(name);
-	if (mygroup == NULL)
-		bb_error_msg_and_die("unknown group name: %s", name);
+char* FAST_FUNC uid2uname_utoa(long uid)
+{
+	char *name = uid2uname(uid);
+	return (name) ? name : utoa(uid);
+}
 
-	return mygroup->gr_gid;
+char* FAST_FUNC gid2group_utoa(long gid)
+{
+	char *name = gid2group(gid);
+	return (name) ? name : utoa(gid);
 }
 
-/* returns a uid given a username */
 long FAST_FUNC xuname2uid(const char *name)
 {
 	struct passwd *myuser;
@@ -87,6 +80,17 @@ long FAST_FUNC xuname2uid(const char *name)
 	return myuser->pw_uid;
 }
 
+long FAST_FUNC xgroup2gid(const char *name)
+{
+	struct group *mygroup;
+
+	mygroup = getgrnam(name);
+	if (mygroup == NULL)
+		bb_error_msg_and_die("unknown group %s", name);
+
+	return mygroup->gr_gid;
+}
+
 unsigned long FAST_FUNC get_ug_id(const char *s,
 		long FAST_FUNC (*xname2id)(const char *))
 {
diff --git a/libbb/procps.c b/libbb/procps.c
index 4d9a95b..c5e40bf 100644
--- a/libbb/procps.c
+++ b/libbb/procps.c
@@ -13,7 +13,7 @@
 
 
 typedef struct unsigned_to_name_map_t {
-	unsigned id;
+	long id;
 	char name[USERNAME_MAX_SIZE];
 } unsigned_to_name_map_t;
 
@@ -52,8 +52,8 @@ static int get_cached(cache_t *cp, unsigned id)
 }
 #endif
 
-typedef char* FAST_FUNC ug_func(char *name, int bufsize, long uid);
-static char* get_cached(cache_t *cp, unsigned id, ug_func* fp)
+static char* get_cached(cache_t *cp, long id,
+			char* FAST_FUNC x2x_utoa(long id))
 {
 	int i;
 	for (i = 0; i < cp->size; i++)
@@ -63,16 +63,16 @@ static char* get_cached(cache_t *cp, unsigned id, ug_func* fp)
 	cp->cache = xrealloc_vector(cp->cache, 2, i);
 	cp->cache[i].id = id;
 	/* Never fails. Generates numeric string if name isn't found */
-	fp(cp->cache[i].name, sizeof(cp->cache[i].name), id);
+	safe_strncpy(cp->cache[i].name, x2x_utoa(id), sizeof(cp->cache[i].name));
 	return cp->cache[i].name;
 }
 const char* FAST_FUNC get_cached_username(uid_t uid)
 {
-	return get_cached(&username, uid, bb_getpwuid);
+	return get_cached(&username, uid, uid2uname_utoa);
 }
 const char* FAST_FUNC get_cached_groupname(gid_t gid)
 {
-	return get_cached(&groupname, gid, bb_getgrgid);
+	return get_cached(&groupname, gid, gid2group_utoa);
 }
 
 
diff --git a/loginutils/passwd.c b/loginutils/passwd.c
index 99fb76e..b156ab5 100644
--- a/loginutils/passwd.c
+++ b/loginutils/passwd.c
@@ -115,7 +115,7 @@ int passwd_main(int argc UNUSED_PARAM, char **argv)
 		bb_show_usage();
 
 	/* Will complain and die if username not found */
-	myname = xstrdup(bb_getpwuid(NULL, -1, myuid));
+	myname = xstrdup(xuid2uname(myuid));
 	name = argv[0] ? argv[0] : myname;
 
 	pw = getpwnam(name);
diff --git a/loginutils/vlock.c b/loginutils/vlock.c
index 0262da5..85f489c 100644
--- a/loginutils/vlock.c
+++ b/loginutils/vlock.c
@@ -38,14 +38,9 @@ int vlock_main(int argc UNUSED_PARAM, char **argv)
 	struct termios term;
 	struct termios oterm;
 	struct vt_mode ovtm;
-	uid_t uid;
 	struct passwd *pw;
-/* XXX: xgetpwuid */
-	uid = getuid();
-	pw = getpwuid(uid);
-	if (pw == NULL)
-		bb_error_msg_and_die("unknown uid %d", (int)uid);
 
+	pw = xgetpwuid(getuid());
 	opt_complementary = "=0"; /* no params! */
 	getopt32(argv, "a");
 
diff --git a/mailutils/sendmail.c b/mailutils/sendmail.c
index 55555c3..b027f94 100644
--- a/mailutils/sendmail.c
+++ b/mailutils/sendmail.c
@@ -172,7 +172,7 @@ int sendmail_main(int argc UNUSED_PARAM, char **argv)
 	// got no sender address? -> use system username as a resort
 	if (!(opts & OPT_f)) {
 		// N.B. IMHO getenv("USER") can be way easily spoofed!
-		G.user = bb_getpwuid(NULL, -1, getuid());
+		G.user = xuid2uname(getuid());
 		opt_from = xasprintf("%s@%s", G.user, domain);
 	}
 	if (ENABLE_FEATURE_CLEAN_UP)
diff --git a/miscutils/crontab.c b/miscutils/crontab.c
index 673b558..9020149 100644
--- a/miscutils/crontab.c
+++ b/miscutils/crontab.c
@@ -130,11 +130,7 @@ int crontab_main(int argc UNUSED_PARAM, char **argv)
 		if (!pas)
 			bb_error_msg_and_die("user %s is not known", user_name);
 	} else {
-/* XXX: xgetpwuid */
-		uid_t my_uid = getuid();
-		pas = getpwuid(my_uid);
-		if (!pas)
-			bb_perror_msg_and_die("unknown uid %d", (int)my_uid);
+		pas = xgetpwuid(getuid());
 	}
 
 #define user_name DONT_USE_ME_BEYOND_THIS_POINT
diff --git a/printutils/lpr.c b/printutils/lpr.c
index 25cbcbc..f21cffd 100644
--- a/printutils/lpr.c
+++ b/printutils/lpr.c
@@ -65,7 +65,7 @@ int lpqr_main(int argc UNUSED_PARAM, char *argv[])
 	const char *server = "localhost"; // server[:port] of printer queue
 	char *hostname;
 	// N.B. IMHO getenv("USER") can be way easily spoofed!
-	const char *user = bb_getpwuid(NULL, -1, getuid());
+	const char *user = xuid2uname(getuid());
 	unsigned job;
 	unsigned opts;
 	int fd;
diff --git a/sysklogd/logger.c b/sysklogd/logger.c
index 6258113..759981c 100644
--- a/sysklogd/logger.c
+++ b/sysklogd/logger.c
@@ -72,22 +72,21 @@ int logger_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int logger_main(int argc, char **argv)
 {
 	char *str_p, *str_t;
+	int opt;
 	int i = 0;
-	char name[80];
 
 	/* Fill out the name string early (may be overwritten later) */
-	bb_getpwuid(name, sizeof(name), geteuid());
-	str_t = name;
+	str_t = uid2uname_utoa(geteuid());
 
 	/* Parse any options */
-	getopt32(argv, "p:st:", &str_p, &str_t);
+	opt = getopt32(argv, "p:st:", &str_p, &str_t);
 
-	if (option_mask32 & 0x2) /* -s */
+	if (opt & 0x2) /* -s */
 		i |= LOG_PERROR;
-	//if (option_mask32 & 0x4) /* -t */
+	//if (opt & 0x4) /* -t */
 	openlog(str_t, i, 0);
 	i = LOG_USER | LOG_NOTICE;
-	if (option_mask32 & 0x1) /* -p */
+	if (opt & 0x1) /* -p */
 		i = pencode(str_p);
 
 	argc -= optind;