Changeset 8219374

Timestamp:

Jul 16, 2011, 12:28:10 AM (14 years ago)

Author:

David Benjamin <davidben@mit.edu>

Branches:

master, release-1.10, release-1.8, release-1.9

Children:

f5f6ec0

Parents:

99ac28a

git-author:

David Benjamin <davidben@mit.edu> (07/10/11 19:11:46)

git-committer:

David Benjamin <davidben@mit.edu> (07/16/11 00:28:10)

Message:

Use getpwnam_r instead of getpwnam

It's re-entrant, so that's probably a good thing in case some other
thread calls getpwnam. More relevantly, Solaris has both a standard and
a non-standard version, and perl redefines getpwnam to a getpwnam_r. We
manage to convince Solaris to use the standard form, but perl doesn't
seem to notice and defines the macro wrong.

So just avoid the function altogether. Seems as reasonable of an excuse
to use the ostensibly better (and infinitely less friendly) one as any.

Files:

• tester.c (modified) (5 diffs)
• util.c (modified) (2 diffs)

tester.c

@@ -4 +4 @@
 #undef WINDOW
 
-#include <errno.h>
 #include <unistd.h>
-#include <pwd.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <sys/types.h>
 
 #undef instr
@@ -136 +133 @@
 {
   int numfailed=0;
-  const char *home;
-  char *s, *path;
-  struct passwd *pw;
+  char *s, *path, *home;
 
   printf("# BEGIN testing owl_util\n");
@@ -274 +269 @@
   g_free(s);
 
-  errno = 0;
-  home = owl_global_get_homedir(&g);
+  home = g_strdup(owl_global_get_homedir(&g));
   s = owl_util_makepath("~");
   FAIL_UNLESS("makepath ~", !strcmp(home, s));
@@ -285 +279 @@
   g_free(s);
   g_free(path);
-
-  errno = 0;
-  pw = getpwnam("root");
-  if (pw) {
-    home = pw->pw_dir;
-  } else {
+  g_free(home);
+
+  home = owl_util_homedir_for_user("root");
+  if (home == NULL) {
     /* Just make some noise so we notice. */
-    home = "<WHAT>";
-    fprintf(stderr, "getpwnam: %s", errno ? strerror(errno) : "No such user");
+    home = g_strdup("<WHAT>");
+    fprintf(stderr, "owl_util_homedir_for_user failed");
   }
 
@@ -305 +297 @@
   g_free(s);
   g_free(path);
+  g_free(home);
 
   /* if (numfailed) printf("*** WARNING: failures encountered with owl_util\n"); */

util.c

@@ -32 +32 @@
 }
 
+CALLER_OWN char *owl_util_homedir_for_user(const char *name)
+{
+  int err;
+  struct passwd pw_buf;
+  struct passwd *pw;
+
+  char *pw_strbuf, *ret;
+  long pw_strbuf_len = sysconf(_SC_GETPW_R_SIZE_MAX);
+  if (pw_strbuf_len < 0) {
+    /* If we really hate ourselves, we can be fancy and loop until we stop
+     * getting ERANGE. For now just pick a random number. */
+    owl_function_error("owl_util_homedir_for_user: Could not get _SC_GETPW_R_SIZE_MAX");
+    pw_strbuf_len = 16384;
+  }
+  pw_strbuf = g_new0(char, pw_strbuf_len);
+  err = getpwnam_r(name, &pw_buf, pw_strbuf, pw_strbuf_len, &pw);
+  if (err) {
+    owl_function_error("getpwuid_r: %s", strerror(err));
+    /* Fall through; pw will be NULL. */
+  }
+  ret = pw ? g_strdup(pw->pw_dir) : NULL;
+  g_free(pw_strbuf);
+  return ret;
+}
+
 /* Return a "nice" version of the path.  Tilde expansion is done, and
  * duplicate slashes are removed.  Caller must free the return.
@@ -55 +80 @@
       /* Someone else's home directory. */
       char *user = g_strndup(in + 1, end - (in + 1));
-      struct passwd *pw = getpwnam(user);
-      g_free(user);
-      if (pw) {
-        out = g_strconcat(pw->pw_dir, end, NULL);
+      char *home = owl_util_homedir_for_user(user);
+      if (home) {
+        out = g_strconcat(home, end, NULL);
       } else {
         out = g_strdup(in);
       }
+      g_free(home);
+      g_free(user);
     }
   } else {