From 546e7c50f1cb9f764eb3dd2af72693c0ac21c58d Mon Sep 17 00:00:00 2001
From: Henrik Hautakoski <henrik@fiktivkod.org>
Date: Fri, 11 Feb 2011 19:17:38 +0100
Subject: [PATCH] path.c: added dirname_s function.

---
 docs/technical/path.txt |  8 ++++++++
 src/path.c              | 26 +++++++++++++++++++++++++-
 src/path.h              |  4 +++-
 test/t_path.c           |  8 +++++---
 4 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/docs/technical/path.txt b/docs/technical/path.txt
index 36db655..6d14051 100644
--- a/docs/technical/path.txt
+++ b/docs/technical/path.txt
@@ -38,3 +38,11 @@ The function performs this type of checks/manipulation:
 +
 Returns `NULL` if 'base' is not an absolute path or 'name' contains a delimiter.
 
+`dirname_s`::
+
+    Safe dirname implementation. works like POSIX dirname with some modifications: +
++
+--
+    * 'slash' may be used to terminate the string with a \'/' character. +
+    * The function will never modify 'path' instead the function will *always* return a static buffer that will be overwritten by subsequent calls.
+--
diff --git a/src/path.c b/src/path.c
index 7ca8bad..ff2031a 100644
--- a/src/path.c
+++ b/src/path.c
@@ -1,6 +1,6 @@
 /* path.c - path handling routines
  * 
- *   Copyright (C) 2010  Henrik Hautakoski <henrik.hautakoski@gmail.com>
+ *   Copyright (C) 2010-2011  Henrik Hautakoski <henrik.hautakoski@gmail.com>
  *
  *   This program is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -12,6 +12,7 @@
  *   so we use funky heap memory based algorithms instead :)
  */
 
+#include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
 #include <sys/types.h>
@@ -67,6 +68,29 @@ int is_dir(const char *path) {
     return 0;
 }
 
+const char* dirname_s(const char *path, int slash) {
+
+    static strbuf_t sb = STRBUF_INIT;
+    
+    strbuf_reduce(&sb, sb.len);
+    strbuf_append_str(&sb, path);
+    strbuf_squeeze(&sb, '/');
+
+    if (sb.len > 1) {
+        if (sb.buf[sb.len-1] == '/')
+            strbuf_reduce(&sb, 1);
+
+        if (!strbuf_rchop(&sb, '/'))
+            strbuf_reduce(&sb, sb.len-1);
+    }
+
+    if (sb.buf[0] != '/')
+        sb.buf[0] = '.';
+    if (slash)
+        strbuf_term(&sb, '/');
+    return sb.buf;
+}
+
 const char *mkpath(const char *fmt, ...) {
 
     static strbuf_t sb = STRBUF_INIT;
diff --git a/src/path.h b/src/path.h
index 054147f..89fe809 100644
--- a/src/path.h
+++ b/src/path.h
@@ -1,6 +1,6 @@
 /* path.h - path handling routines
  * 
- *   Copyright (C) 2010  Henrik Hautakoski <henrik@fiktivkod.org>
+ *   Copyright (C) 2010-2011  Henrik Hautakoski <henrik@fiktivkod.org>
  *
  *   This program is free software: you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -20,6 +20,8 @@ int is_file(const char *path);
 
 int is_dir(const char *path);
 
+const char* dirname_s(const char *path, int slash);
+
 const char* mkpath(const char *fmt, ...);
 
 char* path_normalize(const char *base, const char *name, unsigned dir);
diff --git a/test/t_path.c b/test/t_path.c
index 51fda72..3601b18 100644
--- a/test/t_path.c
+++ b/test/t_path.c
@@ -97,22 +97,24 @@ void test_dirname() {
 
     int i;
 
-    char data[11][2][64] = {
+    char data[13][2][64] = {
         { "", "." },
         { "/", "/" },
         { "///", "/" },
         { ".", "."},
         { "..", "." },
+        { "../", "." },
         { "../../rel", "../.." },
         { "./rel", "." },
+        { "x", "." },
         { "justsomestring", "." },
         { "/usr/src/", "/usr" },
         { "/usr/src///", "/usr" },
         { "/usr/src/linux-2.6.30-r5/drivers", "/usr/src/linux-2.6.30-r5" }
     };
 
-    for(i=0; i < 11; i++)
-        assert_string(dirname(data[i][0]), data[i][1]);
+    for(i=0; i < 12; i++)
+        assert_string(dirname_s(data[i][0], 0), data[i][1]);
 }
 
 int main(int argc, char *argv[]) {