Mercurial > hg > octave-lojdl > gnulib-hg
annotate lib/userspec.c @ 52:d9ca5dc520bf
* system.h [rindex, incl, bcopy, bzero]: Ditto.
* userspec.c [index]: Ditto.
| author | Jim Meyering <jim@meyering.net> |
|---|---|
| date | Mon, 05 Apr 1993 00:53:40 +0000 |
| parents | 41c9d08b09d7 |
| children | 12f81400139d |
| rev | line source |
|---|---|
| 5 | 1 /* userspec.c -- Parse a user and group string. |
| 2 Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc. | |
| 3 | |
| 4 This program is free software; you can redistribute it and/or modify | |
| 5 it under the terms of the GNU General Public License as published by | |
| 6 the Free Software Foundation; either version 2, or (at your option) | |
| 7 any later version. | |
| 8 | |
| 9 This program is distributed in the hope that it will be useful, | |
| 10 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 12 GNU General Public License for more details. | |
| 13 | |
| 14 You should have received a copy of the GNU General Public License | |
| 15 along with this program; if not, write to the Free Software | |
| 16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
| 17 | |
| 18 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */ | |
| 19 | |
| 20 #include <stdio.h> | |
| 21 #include <sys/types.h> | |
| 22 #include <pwd.h> | |
| 23 #include <grp.h> | |
| 24 | |
|
52
d9ca5dc520bf
* system.h [rindex, incl, bcopy, bzero]: Ditto.
Jim Meyering <jim@meyering.net>
parents:
5
diff
changeset
|
25 #if defined(STDC_HEADERS) || defined(HAVE_STRING_H) |
| 5 | 26 #include <string.h> |
|
52
d9ca5dc520bf
* system.h [rindex, incl, bcopy, bzero]: Ditto.
Jim Meyering <jim@meyering.net>
parents:
5
diff
changeset
|
27 #ifndef index |
| 5 | 28 #define index strchr |
|
52
d9ca5dc520bf
* system.h [rindex, incl, bcopy, bzero]: Ditto.
Jim Meyering <jim@meyering.net>
parents:
5
diff
changeset
|
29 #endif |
| 5 | 30 #else |
| 31 #include <strings.h> | |
| 32 #endif | |
| 33 | |
| 34 #ifdef STDC_HEADERS | |
| 35 #include <stdlib.h> | |
| 36 #else | |
| 37 char *malloc (); | |
| 38 #endif | |
| 39 | |
| 40 #ifdef HAVE_UNISTD_H | |
| 41 #include <unistd.h> | |
| 42 #endif | |
| 43 | |
| 44 #ifndef _POSIX_VERSION | |
| 45 struct passwd *getpwnam (); | |
| 46 struct group *getgrnam (); | |
| 47 struct group *getgrgid (); | |
| 48 #endif | |
| 49 | |
| 50 #ifdef _POSIX_SOURCE | |
| 51 #define endpwent() | |
| 52 #define endgrent() | |
| 53 #endif | |
| 54 | |
| 55 #define isdigit(c) ((c) >= '0' && (c) <= '9') | |
| 56 | |
| 57 char *strdup (); | |
| 58 static int isnumber (); | |
| 59 | |
| 60 /* Extract from NAME, which has the form "[user][:.][group]", | |
| 61 a USERNAME, UID U, GROUPNAME, and GID G. | |
| 62 Either user or group, or both, must be present. | |
| 63 If the group is omitted but the ":" or "." separator is given, | |
| 64 use the given user's login group. | |
| 65 | |
| 66 USERNAME and GROUPNAME will be in newly malloc'd memory. | |
| 67 Either one might be NULL instead, indicating that it was not | |
| 68 given and the corresponding numeric ID was left unchanged. | |
| 69 Might write NULs into NAME. | |
| 70 | |
| 71 Return NULL if successful, a static error message string if not. */ | |
| 72 | |
| 73 char * | |
| 74 parse_user_spec (name, uid, gid, username, groupname) | |
| 75 char *name; | |
| 76 uid_t *uid; | |
| 77 gid_t *gid; | |
| 78 char **username, **groupname; | |
| 79 { | |
| 80 static char *tired = "virtual memory exhausted"; | |
| 81 struct passwd *pwd; | |
| 82 struct group *grp; | |
| 83 char *cp; | |
| 84 int use_login_group = 0; | |
| 85 | |
| 86 *username = *groupname = NULL; | |
| 87 | |
| 88 /* Check whether a group is given. */ | |
| 89 cp = index (name, ':'); | |
| 90 if (cp == NULL) | |
| 91 cp = index (name, '.'); | |
| 92 if (cp != NULL) | |
| 93 { | |
| 94 *cp++ = '\0'; | |
| 95 if (*cp == '\0') | |
| 96 { | |
| 97 if (cp == name + 1) | |
| 98 /* Neither user nor group given, just "." or ":". */ | |
| 99 return "can not omit both user and group"; | |
| 100 else | |
| 101 /* "user.". */ | |
| 102 use_login_group = 1; | |
| 103 } | |
| 104 else | |
| 105 { | |
| 106 /* Explicit group. */ | |
| 107 *groupname = strdup (cp); | |
| 108 if (*groupname == NULL) | |
| 109 return tired; | |
| 110 grp = getgrnam (cp); | |
| 111 if (grp == NULL) | |
| 112 { | |
| 113 if (!isnumber (cp)) | |
| 114 return "invalid group"; | |
| 115 *gid = atoi (cp); | |
| 116 } | |
| 117 else | |
| 118 *gid = grp->gr_gid; | |
| 119 endgrent (); /* Save a file descriptor. */ | |
| 120 } | |
| 121 } | |
| 122 | |
| 123 /* Parse the user name, now that any group has been removed. */ | |
| 124 | |
| 125 if (name[0] == '\0') | |
| 126 /* No user name was given, just a group. */ | |
| 127 return NULL; | |
| 128 | |
| 129 *username = strdup (name); | |
| 130 if (*username == NULL) | |
| 131 return tired; | |
| 132 | |
| 133 pwd = getpwnam (name); | |
| 134 if (pwd == NULL) | |
| 135 { | |
| 136 if (!isnumber (name)) | |
| 137 return "invalid user"; | |
| 138 if (use_login_group) | |
| 139 return "cannot get the login group of a numeric UID"; | |
| 140 *uid = atoi (name); | |
| 141 } | |
| 142 else | |
| 143 { | |
| 144 *uid = pwd->pw_uid; | |
| 145 if (use_login_group) | |
| 146 { | |
| 147 *gid = pwd->pw_gid; | |
| 148 grp = getgrgid (pwd->pw_gid); | |
| 149 if (grp == NULL) | |
| 150 { | |
| 151 *groupname = malloc (15); | |
| 152 if (*groupname == NULL) | |
| 153 return tired; | |
| 154 sprintf (*groupname, "%u", pwd->pw_gid); | |
| 155 } | |
| 156 else | |
| 157 { | |
| 158 *groupname = strdup (grp->gr_name); | |
| 159 if (*groupname == NULL) | |
| 160 return tired; | |
| 161 } | |
| 162 endgrent (); | |
| 163 } | |
| 164 } | |
| 165 endpwent (); | |
| 166 return NULL; | |
| 167 } | |
| 168 | |
| 169 /* Return nonzero if STR represents an unsigned decimal integer, | |
| 170 otherwise return 0. */ | |
| 171 | |
| 172 static int | |
| 173 isnumber (str) | |
| 174 char *str; | |
| 175 { | |
| 176 for (; *str; str++) | |
| 177 if (!isdigit (*str)) | |
| 178 return 0; | |
| 179 return 1; | |
| 180 } |