man: implement SECTION parameters

function                                             old     new   delta
man_main                                             807     942    +135
is_section_name                                        -      52     +52
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/0 up/down: 187/0)             Total: 187 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 35 insertions, 6 deletions

diff --git a/miscutils/man.c b/miscutils/man.c
index 61086612a..722f6641e 100644
--- a/miscutils/man.c
+++ b/miscutils/man.c
@@ -13,7 +13,7 @@
 //kbuild:lib-$(CONFIG_MAN) += man.o
 
 //usage:#define man_trivial_usage
-//usage:       "[-aw] MANPAGE..."
+//usage:       "[-aw] [SECTION] MANPAGE[.SECTION]..."
 //usage:#define man_full_usage "\n\n"
 //usage:       "Display manual page\n"
 //usage:     "\n        -a      Display all pages"
@@ -240,10 +240,21 @@ static const char *if_redefined(const char *var, const char *key, const char *li
         return xstrdup(skip_whitespace(line));
 }
 
+static int is_section_name(const char *sections, const char *str)
+{
+        const char *s = strstr(sections, str);
+        if (s) {
+                int l = strlen(str);
+                return (s[l] == ':' || s[l] == '\0');
+        }
+        return 0;
+}
+
 int man_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int man_main(int argc UNUSED_PARAM, char **argv)
 {
         parser_t *parser;
+        char *conf_sec_list;
         char *sec_list;
         char **man_path_list;
         int count_mp;
@@ -255,7 +266,7 @@ int man_main(int argc UNUSED_PARAM, char **argv)
         opt = getopt32(argv, "^+" "aw" "\0" "-1"/*at least one arg*/);
         argv += optind;
 
-        sec_list = xstrdup("0p:1:1p:2:3:3p:4:5:6:7:8:9");
+        conf_sec_list = xstrdup("0p:1:1p:2:3:3p:4:5:6:7:8:9");
 
         count_mp = 0;
         man_path_list = add_MANPATH(NULL, &count_mp,
@@ -285,8 +296,8 @@ int man_main(int argc UNUSED_PARAM, char **argv)
                         man_path_list = add_MANPATH(man_path_list, &count_mp, token[1]);
                 }
                 if (strcmp("MANSECT", token[0]) == 0) {
-                        free(sec_list);
-                        sec_list = xstrdup(token[1]);
+                        free(conf_sec_list);
+                        conf_sec_list = xstrdup(token[1]);
                 }
         }
         config_close(parser);
@@ -311,6 +322,13 @@ int man_main(int argc UNUSED_PARAM, char **argv)
                 G.pager = xasprintf("%s -b -p -x", G.col);
         }
 
+        /* is 1st ARG a SECTION? */
+        sec_list = conf_sec_list;
+        if (is_section_name(conf_sec_list, *argv)) {
+                /* yes */
+                sec_list = *argv++;
+        }
+
         not_found = 0;
         do { /* for each argv[] */
                 const char *cur_path;
@@ -321,11 +339,20 @@ int man_main(int argc UNUSED_PARAM, char **argv)
                         found = show_manpage(*argv, /*man:*/ 1, 0);
                         goto check_found;
                 }
+
+                /* for each MANPATH */
                 cur_mp = 0;
                 while ((cur_path = man_path_list[cur_mp++]) != NULL) {
-                        /* for each MANPATH */
                         const char *cur_sect = sec_list;
-                        do { /* for each section */
+
+                        /* is MANPAGE of the form NAME.SECTION? */
+                        char *sect_ext = strrchr(*argv, '.');
+                        if (sect_ext && is_section_name(conf_sec_list, sect_ext + 1)) {
+                                *sect_ext = '\0';
+                                cur_sect = sect_ext + 1;
+                        }
+
+                        do { /* for each SECTION in cur_sect */
                                 char *next_sect = strchrnul(cur_sect, ':');
                                 int sect_len = next_sect - cur_sect;
                                 char *man_filename;
@@ -352,6 +379,8 @@ int man_main(int argc UNUSED_PARAM, char **argv)
                                 while (*cur_sect == ':')
                                         cur_sect++;
                         } while (*cur_sect);
+
+                        if (sect_ext) *sect_ext = '.';
                 }
  check_found:
                 if (!found) {