shrink tmp array length from 80 to 16.

[gnulib.git] / lib / userspec.c

diff --git a/lib/userspec.c b/lib/userspec.c
index 37b7980..67bde65 100644 (file)
--- a/lib/userspec.c
+++ b/lib/userspec.c
@@ -1,5 +1,5 @@
 /* userspec.c -- Parse a user and group string.
 /* userspec.c -- Parse a user and group string.

-   Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
+   Copyright (C) 1989-1992, 1997, 1998, 2000 Free Software Foundation, Inc.

 
    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
 
    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


@@ -12,20 +12,27 @@
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    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, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

 
 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */
 
 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */

-\f
-#ifdef HAVE_CONFIG_H
-#if defined (CONFIG_BROKETS)
-/* We use <config.h> instead of "config.h" so that a compilation
-   using -I. -I$srcdir will use ./config.h rather than $srcdir/config.h
-   (which it would do because it found this file in $srcdir).  */
-#include <config.h>
-#else
-#include "config.h"
+
+#if HAVE_CONFIG_H
+# include <config.h>

 #endif
 #endif

+
+#ifdef __GNUC__
+# define alloca __builtin_alloca
+#else
+# if HAVE_ALLOCA_H
+#  include <alloca.h>
+# else
+#  ifdef _AIX
+ #  pragma alloca
+#  else
+char *alloca ();
+#  endif
+# endif

 #endif
 
 #include <stdio.h>
 #endif
 
 #include <stdio.h>


@@ -33,24 +40,41 @@
 #include <pwd.h>
 #include <grp.h>
 
 #include <pwd.h>
 #include <grp.h>
 

-#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
-#include <string.h>
-#ifndef index
-#define index strchr
+#if HAVE_SYS_PARAM_H
+# include <sys/param.h>

 #endif
 #endif

-#else
-#include <strings.h>
+
+#if HAVE_LIMITS_H
+# include <limits.h>

 #endif
 
 #endif
 

-#ifdef STDC_HEADERS
-#include <stdlib.h>
+#if HAVE_STRING_H
+# include <string.h>

 #else
 #else

-char *malloc ();
+# include <strings.h>
+# ifndef strchr
+#  define strchr index
+# endif

 #endif
 
 #endif
 

-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
+#if STDC_HEADERS
+# include <stdlib.h>
+#endif
+
+#if HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#include "xalloc.h"
+#include "xstrtol.h"
+
+#if ENABLE_NLS
+# include <libintl.h>
+# define _(Text) gettext (Text)
+#else
+# define _(Text) Text

 #endif
 #endif

+#define N_(Text) Text

 
 #ifndef _POSIX_VERSION
 struct passwd *getpwnam ();
 
 #ifndef _POSIX_VERSION
 struct passwd *getpwnam ();


@@ -58,134 +82,308 @@ struct group *getgrnam ();
 struct group *getgrgid ();
 #endif
 
 struct group *getgrgid ();
 #endif
 

-#ifdef _POSIX_SOURCE
-#define endpwent()
-#define endgrent()
+#ifndef HAVE_ENDGRENT
+# define endgrent() ((void) 0)

 #endif
 
 #endif
 

-#define isdigit(c) ((c) >= '0' && (c) <= '9')
+#ifndef HAVE_ENDPWENT
+# define endpwent() ((void) 0)
+#endif
+
+#ifndef CHAR_BIT
+# define CHAR_BIT 8
+#endif
+
+/* The extra casts work around common compiler bugs.  */
+#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+/* The outer cast is needed to work around a bug in Cray C 5.0.3.0.
+   It is necessary at least when t == time_t.  */
+#define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
+                             ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0))
+#define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t)))
+
+#ifndef UID_T_MAX
+# define UID_T_MAX TYPE_MAXIMUM (uid_t)
+#endif
+
+#ifndef GID_T_MAX
+# define GID_T_MAX TYPE_MAXIMUM (gid_t)
+#endif
+
+/* MAXUID may come from limits.h or sys/params.h.  */
+#ifndef MAXUID
+# define MAXUID UID_T_MAX
+#endif
+#ifndef MAXGID
+# define MAXGID GID_T_MAX
+#endif

 
 

+/* Perform the equivalent of the statement `dest = strdup (src);',
+   but obtaining storage via alloca instead of from the heap.  */
+
+#define V_STRDUP(dest, src)                                            \
+  do                                                                   \
+    {                                                                  \
+      int _len = strlen ((src));                                       \
+      (dest) = (char *) alloca (_len + 1);                             \
+      strcpy (dest, src);                                              \
+    }                                                                  \
+  while (0)
+
+/* ISDIGIT differs from isdigit, as follows:
+   - Its arg may be any int or unsigned int; it need not be an unsigned char.
+   - It's guaranteed to evaluate its argument exactly once.
+   - It's typically faster.
+   Posix 1003.2-1992 section 2.5.2.1 page 50 lines 1556-1558 says that
+   only '0' through '9' are digits.  Prefer ISDIGIT to isdigit unless
+   it's important to use the locale's definition of `digit' even when the
+   host does not conform to Posix.  */
+#define ISDIGIT(c) ((unsigned) (c) - '0' <= 9)
+
+#ifndef strdup

 char *strdup ();
 char *strdup ();

-static int isnumber ();
+#endif
+
+/* Return nonzero if STR represents an unsigned decimal integer,
+   otherwise return 0. */
+
+static int
+is_number (const char *str)
+{
+  for (; *str; str++)
+    if (!ISDIGIT (*str))
+      return 0;
+  return 1;
+}

 
 /* Extract from NAME, which has the form "[user][:.][group]",
    a USERNAME, UID U, GROUPNAME, and GID G.
    Either user or group, or both, must be present.
 
 /* Extract from NAME, which has the form "[user][:.][group]",
    a USERNAME, UID U, GROUPNAME, and GID G.
    Either user or group, or both, must be present.

-   If the group is omitted but the ":" or "." separator is given,
+   If the group is omitted but the ":" separator is given,

    use the given user's login group.
    use the given user's login group.

+   If SPEC_ARG contains a `:', then use that as the separator, ignoring
+   any `.'s.  If there is no `:', but there is a `.', then first look
+   up SPEC_ARG as a login name.  If that look-up fails, then try again
+   interpreting the `.'  as a separator.

 
    USERNAME and GROUPNAME will be in newly malloc'd memory.
    Either one might be NULL instead, indicating that it was not
    given and the corresponding numeric ID was left unchanged.
 
    USERNAME and GROUPNAME will be in newly malloc'd memory.
    Either one might be NULL instead, indicating that it was not
    given and the corresponding numeric ID was left unchanged.

-   Might write NULs into NAME.

 
    Return NULL if successful, a static error message string if not.  */
 
 
    Return NULL if successful, a static error message string if not.  */
 

-char *
-parse_user_spec (name, uid, gid, username, groupname)
-     char *name;
-     uid_t *uid;
-     gid_t *gid;
-     char **username, **groupname;
+const char *
+parse_user_spec (const char *spec_arg, uid_t *uid, gid_t *gid,
+                char **username_arg, char **groupname_arg)

 {
 {

-  static char *tired = "virtual memory exhausted";
+  static const char *E_invalid_user = N_("invalid user");
+  static const char *E_invalid_group = N_("invalid group");
+  static const char *E_bad_spec =
+    N_("cannot get the login group of a numeric UID");
+  static const char *E_cannot_omit_both =
+    N_("cannot omit both user and group");
+
+  const char *error_msg;
+  char *spec;                  /* A copy we can write on.  */

   struct passwd *pwd;
   struct group *grp;
   struct passwd *pwd;
   struct group *grp;

-  char *cp;
-  int use_login_group = 0;
+  char *g, *u, *separator;
+  char *groupname;
+  int maybe_retry = 0;
+  char *dot = NULL;
+
+  error_msg = NULL;
+  *username_arg = *groupname_arg = NULL;
+  groupname = NULL;
+
+  V_STRDUP (spec, spec_arg);

 
 

-  *username = *groupname = NULL;
+  /* Find the POSIX `:' separator if there is one.  */
+  separator = strchr (spec, ':');

 
 

-  /* Check whether a group is given.  */
-  cp = index (name, ':');
-  if (cp == NULL)
-    cp = index (name, '.');
-  if (cp != NULL)
+  /* If there is no colon, then see if there's a `.'.  */
+  if (separator == NULL)

     {
     {

-      *cp++ = '\0';
-      if (*cp == '\0')
+      dot = strchr (spec, '.');
+      /* If there's no colon but there is a `.', then first look up the
+        whole spec, in case it's an OWNER name that includes a dot.
+        If that fails, then we'll try again, but interpreting the `.'
+        as a separator.  */
+      /* FIXME: accepting `.' as the separator is contrary to POSIX.
+        someday we should drop support for this.  */
+      if (dot)
+       maybe_retry = 1;
+    }
+
+ retry:
+
+  /* Replace separator with a NUL.  */
+  if (separator != NULL)
+    *separator = '\0';
+
+  /* Set U and G to non-zero length strings corresponding to user and
+     group specifiers or to NULL.  */
+  u = (*spec == '\0' ? NULL : spec);
+
+  g = (separator == NULL || *(separator + 1) == '\0'
+       ? NULL
+       : separator + 1);
+
+  if (u == NULL && g == NULL)
+    return _(E_cannot_omit_both);
+
+#ifdef __DJGPP__
+  /* Pretend that we are the user U whose group is G.  This makes
+     pwd and grp functions ``know'' about the UID and GID of these.  */
+  if (u && !is_number (u))
+    setenv ("USER", u, 1);
+  if (g && !is_number (g))
+    setenv ("GROUP", g, 1);
+#endif
+
+  if (u != NULL)
+    {
+      pwd = getpwnam (u);
+      if (pwd == NULL)

        {
        {

-         if (cp == name + 1)
-           /* Neither user nor group given, just "." or ":".  */
-           return "can not omit both user and group";
+
+         if (!is_number (u))
+           error_msg = E_invalid_user;

          else
          else

-           /* "user.".  */
-           use_login_group = 1;
+           {
+             int use_login_group;
+             use_login_group = (separator != NULL && g == NULL);
+             if (use_login_group)
+               error_msg = E_bad_spec;
+             else
+               {
+                 unsigned long int tmp_long;
+                 if (xstrtoul (u, NULL, 0, &tmp_long, NULL) != LONGINT_OK
+                     || tmp_long > MAXUID)
+                   return _(E_invalid_user);
+                 printf ("MAXUID: %u\n", (uid_t) MAXUID);
+                 *uid = tmp_long;
+               }
+           }

        }
       else
        {
        }
       else
        {

-         /* Explicit group.  */
-         *groupname = strdup (cp);
-         if (*groupname == NULL)
-           return tired;
-         grp = getgrnam (cp);
-         if (grp == NULL)
+         *uid = pwd->pw_uid;
+         if (g == NULL && separator != NULL)

            {
            {

-             if (!isnumber (cp))
-               return "invalid group";
-             *gid = atoi (cp);
+             /* A separator was given, but a group was not specified,
+                so get the login group.  */
+             *gid = pwd->pw_gid;
+             grp = getgrgid (pwd->pw_gid);
+             if (grp == NULL)
+               {
+                 /* This is enough room to hold the unsigned decimal
+                    representation of any 32-bit quantity and the trailing
+                    zero byte.  */
+                 char uint_buf[21];
+                 sprintf (uint_buf, "%u", (unsigned) (pwd->pw_gid));
+                 V_STRDUP (groupname, uint_buf);
+               }
+             else
+               {
+                 V_STRDUP (groupname, grp->gr_name);
+               }
+             endgrent ();

            }
            }

-         else
-           *gid = grp->gr_gid;
-         endgrent ();          /* Save a file descriptor.  */

        }
        }

+      endpwent ();

     }
 
     }
 

-  /* Parse the user name, now that any group has been removed.  */
-
-  if (name[0] == '\0')
-    /* No user name was given, just a group.  */
-    return NULL;
-
-  *username = strdup (name);
-  if (*username == NULL)
-    return tired;
-
-  pwd = getpwnam (name);
-  if (pwd == NULL)
-    {
-      if (!isnumber (name))
-       return "invalid user";
-      if (use_login_group)
-       return "cannot get the login group of a numeric UID";
-      *uid = atoi (name);
-    }
-  else
+  if (g != NULL && error_msg == NULL)

     {
     {

-      *uid = pwd->pw_uid;
-      if (use_login_group)
+      /* Explicit group.  */
+      grp = getgrnam (g);
+      if (grp == NULL)

        {
        {

-         *gid = pwd->pw_gid;
-         grp = getgrgid (pwd->pw_gid);
-         if (grp == NULL)
+         if (!is_number (g))
+           error_msg = E_invalid_group;
+         else

            {
            {

-             *groupname = malloc (15);
-             if (*groupname == NULL)
-               return tired;
-             sprintf (*groupname, "%u", (unsigned) (pwd->pw_gid));
+             unsigned long int tmp_long;
+             if (xstrtoul (u, NULL, 0, &tmp_long, NULL) != LONGINT_OK
+                 || tmp_long > MAXGID)
+               return _(E_invalid_group);
+             *gid = tmp_long;

            }
            }

-         else
+       }
+      else
+       *gid = grp->gr_gid;
+      endgrent ();             /* Save a file descriptor.  */
+
+      if (error_msg == NULL)
+       V_STRDUP (groupname, g);
+    }
+
+  if (error_msg == NULL)
+    {
+      if (u != NULL)
+       {
+         *username_arg = strdup (u);
+         if (*username_arg == NULL)
+           error_msg = xalloc_msg_memory_exhausted;
+       }
+
+      if (groupname != NULL && error_msg == NULL)
+       {
+         *groupname_arg = strdup (groupname);
+         if (*groupname_arg == NULL)

            {
            {

-             *groupname = strdup (grp->gr_name);
-             if (*groupname == NULL)
-               return tired;
+             if (*username_arg != NULL)
+               {
+                 free (*username_arg);
+                 *username_arg = NULL;
+               }
+             error_msg = xalloc_msg_memory_exhausted;

            }
            }

-         endgrent ();

        }
     }
        }
     }

-  endpwent ();
-  return NULL;
+
+  if (error_msg && maybe_retry)
+    {
+      maybe_retry = 0;
+      separator = dot;
+      error_msg = NULL;
+      goto retry;
+    }
+
+  return _(error_msg);

 }
 
 }
 

-/* Return nonzero if STR represents an unsigned decimal integer,
-   otherwise return 0. */
+#ifdef TEST

 
 

-static int
-isnumber (str)
-     char *str;
+# define NULL_CHECK(s) ((s) == NULL ? "(null)" : (s))
+
+int
+main (int argc, char **argv)

 {
 {

-  for (; *str; str++)
-    if (!isdigit (*str))
-      return 0;
-  return 1;
+  int i;
+
+  for (i = 1; i < argc; i++)
+    {
+      const char *e;
+      char *username, *groupname;
+      uid_t uid;
+      gid_t gid;
+      char *tmp;
+
+      tmp = strdup (argv[i]);
+      e = parse_user_spec (tmp, &uid, &gid, &username, &groupname);
+      free (tmp);
+      printf ("%s: %u %u %s %s %s\n",
+             argv[i],
+             (unsigned int) uid,
+             (unsigned int) gid,
+             NULL_CHECK (username),
+             NULL_CHECK (groupname),
+             NULL_CHECK (e));
+    }
+
+  exit (0);

 }
 }

+
+#endif