X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fgetusershell.c;h=c026ec0a9c2482b8bf077c97b0f55028fb200d34;hb=265465e1145409720be48d30b6277a59151d293a;hp=730d1b5c04bc19ba8d226d4a4aefc5c92feb3eea;hpb=89f0bcabccee0db1ef28172dec5224be73142d44;p=gnulib.git diff --git a/lib/getusershell.c b/lib/getusershell.c index 730d1b5c0..c026ec0a9 100644 --- a/lib/getusershell.c +++ b/lib/getusershell.c @@ -1,5 +1,5 @@ /* getusershell.c -- Return names of valid user shells. - Copyright (C) 1991, 1997 Free Software Foundation, Inc. + Copyright (C) 1991, 1997, 2000, 2001, 2003 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 @@ -22,12 +22,20 @@ #endif #ifndef SHELLS_FILE +# ifndef __DJGPP__ /* File containing a list of nonrestricted shells, one per line. */ -# define SHELLS_FILE "/etc/shells" +# define SHELLS_FILE "/etc/shells" +# else +/* This is a horrible kludge. Isn't there a better way? */ +# define SHELLS_FILE "/dev/env/DJDIR/etc/shells" +# endif #endif #include +#include #include +#include "unlocked-io.h" +#include "xalloc.h" #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII)) # define IN_CTYPE_DOMAIN(c) 1 @@ -37,26 +45,25 @@ #define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c)) -#ifdef STDC_HEADERS -# include +static size_t readname (char **, size_t *, FILE *); + +#if ! defined ADDITIONAL_DEFAULT_SHELLS && defined __MSDOS__ +# define ADDITIONAL_DEFAULT_SHELLS \ + "c:/dos/command.com", "c:/windows/command.com", "c:/command.com", #else -char *malloc (); -char *realloc (); +# define ADDITIONAL_DEFAULT_SHELLS /* empty */ #endif -char *xstrdup (); - -static int readname (); - /* List of shells to use if the shells file is missing. */ static char const* const default_shells[] = { + ADDITIONAL_DEFAULT_SHELLS "/bin/sh", "/bin/csh", "/usr/bin/sh", "/usr/bin/csh", NULL }; /* Index of the next shell in `default_shells' to return. 0 means we are not using `default_shells'. */ -static int default_index = 0; +static size_t default_index = 0; /* Input stream from the shells file. */ static FILE *shellstream = NULL; @@ -65,7 +72,7 @@ static FILE *shellstream = NULL; static char *line = NULL; /* Number of bytes allocated for `line'. */ -static int line_size = 0; +static size_t line_size = 0; /* Return an entry from the shells file, ignoring comment lines. If the file doesn't exist, use the list in DEFAULT_SHELLS (above). @@ -73,7 +80,7 @@ static int line_size = 0; Return NULL if there are no more entries. */ char * -getusershell () +getusershell (void) { if (default_index > 0) { @@ -105,19 +112,17 @@ getusershell () /* Rewind the shells file. */ void -setusershell () +setusershell (void) { default_index = 0; - if (shellstream == NULL) - shellstream = fopen (SHELLS_FILE, "r"); - else - fseek (shellstream, 0L, 0); + if (shellstream) + rewind (shellstream); } /* Close the shells file. */ void -endusershell () +endusershell (void) { if (shellstream) { @@ -126,60 +131,27 @@ endusershell () } } -/* Allocate N bytes of memory dynamically, with error checking. */ - -static char * -xmalloc (n) - unsigned n; -{ - char *p; - - p = malloc (n); - if (p == 0) - { - fprintf (stderr, "virtual memory exhausted\n"); - exit (1); - } - return p; -} - -/* Reallocate space P to size N, with error checking. */ - -static char * -xrealloc (p, n) - char *p; - unsigned n; -{ - p = realloc (p, n); - if (p == 0) - { - fprintf (stderr, "virtual memory exhausted\n"); - exit (1); - } - return p; -} - /* Read a line from STREAM, removing any newline at the end. Place the result in *NAME, which is malloc'd and/or realloc'd as necessary and can start out NULL, and whose size is passed and returned in *SIZE. - Return the number of characters placed in *NAME + Return the number of bytes placed in *NAME if some nonempty sequence was found, otherwise 0. */ -static int -readname (name, size, stream) - char **name; - int *size; - FILE *stream; +static size_t +readname (char **name, size_t *size, FILE *stream) { int c; - int name_index = 0; + size_t name_index = 0; if (*name == NULL) { - *size = 10; - *name = (char *) xmalloc (*size); + /* The initial size must be a power of two, so that the overflow + check works. */ + *size = 16; + + *name = xmalloc (*size); } /* Skip blank space. */ @@ -189,10 +161,12 @@ readname (name, size, stream) while (c != EOF && !ISSPACE (c)) { (*name)[name_index++] = c; - while (name_index >= *size) + if (*size < name_index) { *size *= 2; - *name = (char *) xrealloc (*name, *size); + if (! *size) + xalloc_die (); + *name = xrealloc (*name, *size); } c = getc (stream); } @@ -201,7 +175,8 @@ readname (name, size, stream) } #ifdef TEST -main () +int +main (void) { char *s;