diff mbox

[review,v4] localedef: Add verbose messages for failure paths.

Message ID 20191210211525.2415420AF6@gnutoolchain-gerrit.osci.io
State New
Headers show

Commit Message

Simon Marchi (Code Review) Dec. 10, 2019, 9:15 p.m. UTC
Change URL: https://gnutoolchain-gerrit.osci.io/r/c/glibc/+/303
......................................................................

localedef: Add verbose messages for failure paths.

During testing of localedef running in a minimal container
there were several error cases which were hard to diagnose
since they appeared as strerror (errno) values printed by
the higher level functions.  This change adds three new
verbose messages for potential failure paths.  The new
messages give the user the opportunity to use -v and display
additional information about why localedef might be failing.
I found these messages useful myself while writing a localedef
container test for --no-hard-links.

Change-Id: I28b9f680711ff00252a2cb15625b774cc58ecb9d
---
A include/programs/xasprintf.h
M locale/Makefile
M locale/programs/localedef.c
M locale/programs/localedef.h
A locale/programs/xasprintf.c
5 files changed, 120 insertions(+), 52 deletions(-)

Comments

DJ Delorie Dec. 10, 2019, 9:34 p.m. UTC | #1
"Carlos O'Donell (Code Review)" <gerrit@gnutoolchain-gerrit.osci.io>
writes:
> A locale/programs/xasprintf.c

We already have one in support/xasprintf.c.  We shouldn't have two
copies in the tree, somehow.
Carlos O'Donell Dec. 12, 2019, 6:15 p.m. UTC | #2
On 12/10/19 4:34 PM, DJ Delorie wrote:
> "Carlos O'Donell (Code Review)" <gerrit@gnutoolchain-gerrit.osci.io>
> writes:
>> A locale/programs/xasprintf.c
> 
> We already have one in support/xasprintf.c.  We shouldn't have two
> copies in the tree, somehow.

This was discussed originally, and we can't or rather don't want to
use the support/xasprintf.c since it may need to be built differently
from what we need for a distributed binary.

I would like to keep support/* infrastructure directly decoupled from
the installed programs we build.

Yes that means having possibly two xmalloc's and two xasprintf's.

For example the runtime implementation needs gettext and translation
for the error message, and calls error.

The support implementation doesn't need translations and can include
a bunch more headers and use FAIL_EXIT1.

I would really like to consider them distinct implementation for
distinct operating environments.
Florian Weimer Dec. 13, 2019, 12:33 p.m. UTC | #3
* Carlos O'Donell:

> On 12/10/19 4:34 PM, DJ Delorie wrote:
>> "Carlos O'Donell (Code Review)" <gerrit@gnutoolchain-gerrit.osci.io>
>> writes:
>>> A locale/programs/xasprintf.c
>> 
>> We already have one in support/xasprintf.c.  We shouldn't have two
>> copies in the tree, somehow.
>
> This was discussed originally, and we can't or rather don't want to
> use the support/xasprintf.c since it may need to be built differently
> from what we need for a distributed binary.
>
> I would like to keep support/* infrastructure directly decoupled from
> the installed programs we build.
>
> Yes that means having possibly two xmalloc's and two xasprintf's.
>
> For example the runtime implementation needs gettext and translation
> for the error message, and calls error.
>
> The support implementation doesn't need translations and can include
> a bunch more headers and use FAIL_EXIT1.
>
> I would really like to consider them distinct implementation for
> distinct operating environments.

I agree.  It's not ideal, but there isn't that much commonality between
the implementations anyway.

Florian
diff mbox

Patch

diff --git a/include/programs/xasprintf.h b/include/programs/xasprintf.h
new file mode 100644
index 0000000..53193ba
--- /dev/null
+++ b/include/programs/xasprintf.h
@@ -0,0 +1,24 @@ 
+/* asprintf with out of memory checking
+   Copyright (C) 2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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 the Free Software Foundation; version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <https://www.gnu.org/licenses/>.  */
+
+#ifndef _XASPRINTF_H
+#define _XASPRINTF_H	1
+
+extern char *xasprintf (const char *format, ...)
+    __attribute__ ((__format__ (__printf__, 1, 2), __warn_unused_result__));
+
+#endif /* xasprintf.h */
diff --git a/locale/Makefile b/locale/Makefile
index 1a19b6f..943df35 100644
--- a/locale/Makefile
+++ b/locale/Makefile
@@ -56,7 +56,7 @@ 
 localedef-aux		:= md5
 locale-modules		:= locale locale-spec
 lib-modules		:= charmap-dir simple-hash xmalloc xstrdup \
-			   record-status
+			   record-status xasprintf
 
 
 GPERF = gperf
diff --git a/locale/programs/localedef.c b/locale/programs/localedef.c
index 3dcf15f..b926117 100644
--- a/locale/programs/localedef.c
+++ b/locale/programs/localedef.c
@@ -434,20 +434,16 @@ 
     {
     case ARGP_KEY_HELP_EXTRA:
       /* We print some extra information.  */
-      if (asprintf (&tp, gettext ("\
+      tp = xasprintf (gettext ("\
 For bug reporting instructions, please see:\n\
-%s.\n"), REPORT_BUGS_TO) < 0)
-	return NULL;
-      if (asprintf (&cp, gettext ("\
+%s.\n"), REPORT_BUGS_TO);
+      cp = xasprintf (gettext ("\
 System's directory for character maps : %s\n\
 		       repertoire maps: %s\n\
 		       locale path    : %s\n\
 %s"),
-		    CHARMAP_PATH, REPERTOIREMAP_PATH, LOCALE_PATH, tp) < 0)
-	{
-	  free (tp);
-	  return NULL;
-	}
+		    CHARMAP_PATH, REPERTOIREMAP_PATH, LOCALE_PATH, tp);
+      free (tp);
       return cp;
     default:
       break;
@@ -477,15 +473,13 @@ 
 }
 
 
-/* The parameter to localedef describes the output path.  If it does
-   contain a '/' character it is a relative path.  Otherwise it names the
-   locale this definition is for.  */
+/* The parameter to localedef describes the output path.  If it does contain a
+   '/' character it is a relative path.  Otherwise it names the locale this
+   definition is for.   The returned path must be freed by the caller. */
 static const char *
 construct_output_path (char *path)
 {
-  const char *normal = NULL;
   char *result;
-  char *endp;
 
   if (strchr (path, '/') == NULL)
     {
@@ -493,50 +487,44 @@ 
 	 contains a reference to the codeset.  This should be
 	 normalized.  */
       char *startp;
+      char *endp = NULL;
+      const char *normal = NULL;
 
       startp = path;
-      /* We must be prepared for finding a CEN name or a location of
-	 the introducing `.' where it is not possible anymore.  */
+      /* Either we have a '@' which starts a CEN name or '.' which starts the
+	 codeset specification.  The CEN name starts with '@' and may also have
+	 a codeset specification, but we do not normalize the string after '@'.
+	 If we only find the codeset specification then we normalize only the codeset
+	 specification (but not anything after a subsequent '@').  */
       while (*startp != '\0' && *startp != '@' && *startp != '.')
 	++startp;
       if (*startp == '.')
 	{
 	  /* We found a codeset specification.  Now find the end.  */
 	  endp = ++startp;
+
+	  /* Stop at the first '@', and don't normalize anything past that.  */
 	  while (*endp != '\0' && *endp != '@')
 	    ++endp;
 
 	  if (endp > startp)
 	    normal = normalize_codeset (startp, endp - startp);
 	}
-      else
-	/* This is to keep gcc quiet.  */
-	endp = NULL;
 
-      /* We put an additional '\0' at the end of the string because at
-	 the end of the function we need another byte for the trailing
-	 '/'.  */
-      ssize_t n;
       if (normal == NULL)
-	n = asprintf (&result, "%s%s/%s%c", output_prefix ?: "",
-		      COMPLOCALEDIR, path, '\0');
+	result = xasprintf ("%s%s/%s/", output_prefix ?: "",
+			    COMPLOCALEDIR, path);
       else
-	n = asprintf (&result, "%s%s/%.*s%s%s%c",
-		      output_prefix ?: "", COMPLOCALEDIR,
-		      (int) (startp - path), path, normal, endp, '\0');
-
-      if (n < 0)
-	return NULL;
-
-      endp = result + n - 1;
+	result = xasprintf ("%s%s/%.*s%s%s/",
+			    output_prefix ?: "", COMPLOCALEDIR,
+			    (int) (startp - path), path, normal, endp ?: "");
+      /* Free the allocated normalized codeset name.  */
+      free ((char *) normal);
     }
   else
     {
-      /* This is a user path.  Please note the additional byte in the
-	 memory allocation.  */
-      size_t len = strlen (path) + 1;
-      result = xmalloc (len + 1);
-      endp = mempcpy (result, path, len) - 1;
+      /* This is a user path.  */
+      result = xasprintf ("%s/", path);
 
       /* If the user specified an output path we cannot add the output
 	 to the archive.  */
@@ -546,24 +534,40 @@ 
   errno = 0;
 
   if (no_archive && euidaccess (result, W_OK) == -1)
-    /* Perhaps the directory does not exist now.  Try to create it.  */
-    if (errno == ENOENT)
-      {
-	errno = 0;
-	if (mkdir (result, 0777) < 0)
-	  return NULL;
-      }
-
-  *endp++ = '/';
-  *endp = '\0';
+    {
+      /* Perhaps the directory does not exist now.  Try to create it.  */
+      if (errno == ENOENT)
+	{
+	  errno = 0;
+	  if (mkdir (result, 0777) < 0)
+	    {
+	      record_verbose (stderr,
+			      _("cannot create output path \"%s\": %s"),
+			      result, strerror (errno));
+	      free (result);
+	      return NULL;
+	    }
+	}
+      else
+	record_verbose (stderr,
+			_("no write permission to output path \"%s\": %s"),
+			result, strerror (errno));
+    }
 
   return result;
 }
 
 
-/* Normalize codeset name.  There is no standard for the codeset
-   names.  Normalization allows the user to use any of the common
-   names.  */
+/* Normalize codeset name.  There is no standard for the codeset names.
+   Normalization allows the user to use any of the common names e.g. UTF-8,
+   utf-8, utf8, UTF8 etc.
+
+   We normalize using the following rules:
+   - Remove all non-alpha-numeric characters
+   - Lowercase all cahracters.
+   - If there are only digits assume it's an ISO standard and prefix with 'iso'
+
+   We return the normalized string which needs to be freed by free.  */
 static const char *
 normalize_codeset (const char *codeset, size_t name_len)
 {
@@ -573,6 +577,7 @@ 
   char *wp;
   size_t cnt;
 
+  /* Compute the length of only the alpha-numeric characters.  */
   for (cnt = 0; cnt < name_len; ++cnt)
     if (isalnum (codeset[cnt]))
       {
@@ -582,6 +587,8 @@ 
 	  only_digit = 0;
       }
 
+  /* If there were only digits we assume it's an ISO standard and we will
+     prefix with 'iso' so include space for that.  */
   retval = (char *) malloc ((only_digit ? 3 : 0) + len + 1);
 
   if (retval != NULL)
@@ -592,6 +599,7 @@ 
 	wp = retval;
 
       for (cnt = 0; cnt < name_len; ++cnt)
+	/* Lowercase all characters. */
 	if (isalpha (codeset[cnt]))
 	  *wp++ = tolower (codeset[cnt]);
 	else if (isdigit (codeset[cnt]))
@@ -600,6 +608,7 @@ 
       *wp = '\0';
     }
 
+  /* Return allocated and converted name for caller to free.  */
   return (const char *) retval;
 }
 
diff --git a/locale/programs/localedef.h b/locale/programs/localedef.h
index 80da0b0..ad2a927 100644
--- a/locale/programs/localedef.h
+++ b/locale/programs/localedef.h
@@ -123,6 +123,7 @@ 
 
 /* Prototypes for a few program-wide used functions.  */
 #include <programs/xmalloc.h>
+#include <programs/xasprintf.h>
 
 
 /* Mark given locale as to be read.  */
diff --git a/locale/programs/xasprintf.c b/locale/programs/xasprintf.c
new file mode 100644
index 0000000..efc91a9
--- /dev/null
+++ b/locale/programs/xasprintf.c
@@ -0,0 +1,34 @@ 
+/* asprintf with out of memory checking
+   Copyright (C) 2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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 the Free Software Foundation; version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <https://www.gnu.org/licenses/>.  */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <libintl.h>
+#include <error.h>
+
+char *
+xasprintf (const char *format, ...)
+{
+  va_list ap;
+  va_start (ap, format);
+  char *result;
+  if (vasprintf (&result, format, ap) < 0)
+    error (EXIT_FAILURE, 0, _("memory exhausted"));
+  va_end (ap);
+  return result;
+}