[v2] iconvconfig: Fix behaviour with --prefix [BZ #28199]

Message ID 20210913132635.67314-1-siddhesh@sourceware.org
State Superseded
Headers
Series [v2] iconvconfig: Fix behaviour with --prefix [BZ #28199] |

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Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent
dj/TryBot-32bit success Build for i686

Commit Message

Siddhesh Poyarekar Sept. 13, 2021, 1:26 p.m. UTC
  The consolidation of configuration parsing broke behaviour with
--prefix, where the prefix bled into the modules cache.  Accept a
prefix which, when non-NULL, is prepended to the path when looking for
configuration files but only the original directory is added to the
modules cache.

This has no effect on the codegen of gconv_conf since it passes NULL.

Reported-by: Patrick McCarty <patrick.mccarty@intel.com>
Reported-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
---
Changes from v1:
- Dropped the Signed-off-by that I added accidentally.

 iconv/gconv_conf.c         |  2 +-
 iconv/gconv_parseconfdir.h | 21 +++++++++++++++------
 iconv/iconvconfig.c        | 16 ++++++++++++----
 3 files changed, 28 insertions(+), 11 deletions(-)
  

Comments

Andreas Schwab Sept. 13, 2021, 2:03 p.m. UTC | #1
On Sep 13 2021, Siddhesh Poyarekar via Libc-alpha wrote:

> diff --git a/iconv/gconv_parseconfdir.h b/iconv/gconv_parseconfdir.h
> index 2f062689ec..38ffa9353a 100644
> --- a/iconv/gconv_parseconfdir.h
> +++ b/iconv/gconv_parseconfdir.h
> @@ -38,8 +38,9 @@
>  
>  /* Name of the file containing the module information in the directories
>     along the path.  */
> -static const char gconv_conf_filename[] = "gconv-modules";
> -static const char gconv_conf_dirname[] = "gconv-modules.d";
> +#define GCONV_CONF_FILENAME "gconv-modules"
> +static const char gconv_conf_filename[] = GCONV_CONF_FILENAME;
> +static const char gconv_conf_dirname[] = GCONV_CONF_FILENAME ".d";

Do we really need gconv_conf_dirname?  It's only used inside sizeof, and
gconv_parseconfdir already knows that it's gconv_conf_filename + ".d".

Andreas.
  
Siddhesh Poyarekar Sept. 13, 2021, 2:10 p.m. UTC | #2
On 9/13/21 7:33 PM, Andreas Schwab wrote:
> On Sep 13 2021, Siddhesh Poyarekar via Libc-alpha wrote:
> 
>> diff --git a/iconv/gconv_parseconfdir.h b/iconv/gconv_parseconfdir.h
>> index 2f062689ec..38ffa9353a 100644
>> --- a/iconv/gconv_parseconfdir.h
>> +++ b/iconv/gconv_parseconfdir.h
>> @@ -38,8 +38,9 @@
>>   
>>   /* Name of the file containing the module information in the directories
>>      along the path.  */
>> -static const char gconv_conf_filename[] = "gconv-modules";
>> -static const char gconv_conf_dirname[] = "gconv-modules.d";
>> +#define GCONV_CONF_FILENAME "gconv-modules"
>> +static const char gconv_conf_filename[] = GCONV_CONF_FILENAME;
>> +static const char gconv_conf_dirname[] = GCONV_CONF_FILENAME ".d";
> 
> Do we really need gconv_conf_dirname?  It's only used inside sizeof, and
> gconv_parseconfdir already knows that it's gconv_conf_filename + ".d".
> 

OK, I'll get rid of it.

Siddhesh
  

Patch

diff --git a/iconv/gconv_conf.c b/iconv/gconv_conf.c
index 09ffe023f9..077082af66 100644
--- a/iconv/gconv_conf.c
+++ b/iconv/gconv_conf.c
@@ -477,7 +477,7 @@  __gconv_read_conf (void)
   __gconv_get_path ();
 
   for (cnt = 0; __gconv_path_elem[cnt].name != NULL; ++cnt)
-    gconv_parseconfdir (__gconv_path_elem[cnt].name,
+    gconv_parseconfdir (NULL, __gconv_path_elem[cnt].name,
 			__gconv_path_elem[cnt].len);
 #endif
 
diff --git a/iconv/gconv_parseconfdir.h b/iconv/gconv_parseconfdir.h
index 2f062689ec..38ffa9353a 100644
--- a/iconv/gconv_parseconfdir.h
+++ b/iconv/gconv_parseconfdir.h
@@ -38,8 +38,9 @@ 
 
 /* Name of the file containing the module information in the directories
    along the path.  */
-static const char gconv_conf_filename[] = "gconv-modules";
-static const char gconv_conf_dirname[] = "gconv-modules.d";
+#define GCONV_CONF_FILENAME "gconv-modules"
+static const char gconv_conf_filename[] = GCONV_CONF_FILENAME;
+static const char gconv_conf_dirname[] = GCONV_CONF_FILENAME ".d";
 
 static void add_alias (char *);
 static void add_module (char *, const char *, size_t, int);
@@ -110,19 +111,27 @@  read_conf_file (const char *filename, const char *directory, size_t dir_len)
   return true;
 }
 
+/* Prefix DIR (with length DIR_LEN) with PREFIX if the latter is non-NULL and
+   parse configuration in it.  */
+
 static __always_inline bool
-gconv_parseconfdir (const char *dir, size_t dir_len)
+gconv_parseconfdir (const char *prefix, const char *dir, size_t dir_len)
 {
   /* No slash needs to be inserted between dir and gconv_conf_filename;
      dir already ends in a slash.  */
-  char *buf = malloc (dir_len + sizeof (gconv_conf_dirname));
+  size_t buflen = dir_len + sizeof (gconv_conf_dirname);
+  char *buf = malloc (buflen + (prefix != NULL ? strlen (prefix) : 0));
+  char *cp = buf;
   bool found = false;
 
   if (buf == NULL)
     return false;
 
-  char *cp = mempcpy (mempcpy (buf, dir, dir_len), gconv_conf_filename,
-		      sizeof (gconv_conf_filename));
+  if (prefix != NULL)
+    cp = stpcpy (cp, prefix);
+
+  cp = mempcpy (mempcpy (cp, dir, dir_len), gconv_conf_filename,
+		sizeof (gconv_conf_filename));
 
   /* Read the gconv-modules configuration file first.  */
   found = read_conf_file (buf, dir, dir_len);
diff --git a/iconv/iconvconfig.c b/iconv/iconvconfig.c
index fd61cf27fe..a89b62e784 100644
--- a/iconv/iconvconfig.c
+++ b/iconv/iconvconfig.c
@@ -652,13 +652,21 @@  add_module (char *rp, const char *directory,
 static int
 handle_dir (const char *dir)
 {
+  char *newp = NULL;
   size_t dirlen = strlen (dir);
   bool found = false;
 
-  char *fulldir = xasprintf ("%s%s%s", dir[0] == '/' ? prefix : "",
-			     dir, dir[dirlen - 1] != '/' ? "/" : "");
+  /* End directory path with a '/' if it doesn't already.  */
+  if (dir[dirlen - 1] != '/')
+    {
+      newp = xmalloc (dirlen + 2);
+      memcpy (newp, dir, dirlen);
+      newp[dirlen++] = '/';
+      newp[dirlen] = '\0';
+      dir = newp;
+    }
 
-  found = gconv_parseconfdir (fulldir, strlen (fulldir));
+  found = gconv_parseconfdir (dir[0] == '/' ? prefix : NULL, dir, dirlen);
 
   if (!found)
     {
@@ -670,7 +678,7 @@  handle_dir (const char *dir)
 	     "configuration files with names ending in .conf.");
     }
 
-  free (fulldir);
+  free (newp);
 
   return found ? 0 : 1;
 }