[or-cvs] Resolve FIXME items: make expand_filename handle ~ and ~use...

[Nick Mathewson]

Update of /home/or/cvsroot/src/common
In directory moria.mit.edu:/tmp/cvs-serv32065/src/common

Modified Files:
	util.c compat.c compat.h 
Log Message:
Resolve FIXME items: make expand_filename handle ~ and ~username

Index: util.c
===================================================================
RCS file: /home/or/cvsroot/src/common/util.c,v
retrieving revision 1.176
retrieving revision 1.177
diff -u -d -r1.176 -r1.177
--- util.c	9 Nov 2004 20:04:00 -0000	1.176
+++ util.c	10 Nov 2004 14:23:31 -0000	1.177
@@ -958,22 +958,50 @@
 char *expand_filename(const char *filename)
 {
   tor_assert(filename);
-  /* XXXX Should eventually check for ~username/ */
-  if (!strncmp(filename,"~/",2)) {
+  if (*filename == '~') {
     size_t len;
-    const char *home = getenv("HOME");
-    char *result;
-    if (!home) {
-      log_fn(LOG_WARN, "Couldn't find $HOME environment variable while expanding %s", filename);
-      return NULL;
+    char *home, *result;
+    const char *rest;
+
+    if (filename[1] == '/' || filename[1] == '\0') {
+      home = getenv("HOME");
+      if (!home) {
+        log_fn(LOG_WARN, "Couldn't find $HOME environment variable while expanding %s", filename);
+        return NULL;
+      }
+      home = tor_strdup(home);
+      rest = strlen(filename)>=2?(filename+2):NULL;
+    } else {
+#ifdef HAVE_PWD_H
+      char *username, *slash;
+      slash = strchr(filename, '/');
+      if (slash)
+        username = tor_strndup(filename+1,slash-filename-1);
+      else
+        username = tor_strdup(filename+1);
+      if (!(home = get_user_homedir(username))) {
+        log_fn(LOG_WARN,"Couldn't get homedir for %s",username);
+        tor_free(username);
+        return NULL;
+      }
+      tor_free(username);
+      rest = slash ? (slash+1) : NULL;
+#else
+      log_fn(LOG_WARN, "Couldn't expend homedir on system without pwd.h");
+      return tor_strdup(filename);
+#endif
     }
-    /* minus two characters for ~/, plus one for /, plus one for NUL.
+    tor_assert(home);
+    /* Remove trailing slash. */
+    if (strlen(home)>1 && !strcmpend(home,"/")) {
+      home[strlen(home)-1] = '\0';
+    }
+    /* Plus one for /, plus one for NUL.
      * Round up to 16 in case we can't do math. */
-    len = strlen(home)+strlen(filename)+16;
+    len = strlen(home)+strlen(rest)+16;
     result = tor_malloc(len);
-    tor_snprintf(result,len,"%s%s%s",home,
-                 (!strcmpend(home, "/")) ? "" : "/",
-                 filename+2);
+    tor_snprintf(result,len,"%s/%s",home,rest?rest:"");
+    tor_free(home);
     return result;
   } else {
     return tor_strdup(filename);

Index: compat.c
===================================================================
RCS file: /home/or/cvsroot/src/common/compat.c,v
retrieving revision 1.9
retrieving revision 1.10
diff -u -d -r1.9 -r1.10
--- compat.c	10 Nov 2004 09:09:15 -0000	1.9
+++ compat.c	10 Nov 2004 14:23:31 -0000	1.10
@@ -390,6 +390,23 @@
   return -1;
 }
 
+#ifdef HAVE_PWD_H
+/** Allocate and return a string containing the home directory for the
+ * user <b>username</b>. Only works on posix-like systems */
+char *
+get_user_homedir(const char *username)
+{
+  struct passwd *pw;
+  tor_assert(username);
+
+  if (!(pw = getpwnam(username))) {
+    log_fn(LOG_ERR,"User '%s' not found.", username);
+    return NULL;
+  }
+  return tor_strdup(pw->pw_dir);
+}
+#endif
+
 /** Set *addr to the IP address (in dotted-quad notation) stored in c.
  * Return 1 on success, 0 if c is badly formatted.  (Like inet_aton(c,addr),
  * but works on Windows and Solaris.)

Index: compat.h
===================================================================
RCS file: /home/or/cvsroot/src/common/compat.h,v
retrieving revision 1.6
retrieving revision 1.7
diff -u -d -r1.6 -r1.7
--- compat.h	4 Nov 2004 22:33:20 -0000	1.6
+++ compat.h	10 Nov 2004 14:23:31 -0000	1.7
@@ -164,6 +164,9 @@
 
 int set_max_file_descriptors(unsigned int required_min);
 int switch_id(char *user, char *group);
+#ifdef HAVE_PWD_H
+char *get_user_homedir(const char *username);
+#endif
 
 int spawn_func(int (*func)(void *), void *data);
 void spawn_exit(void);