busybox/chmod.c
1999-10-05 16:24:54 +00:00

164 lines
3.1 KiB
C

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/stat.h>
#include "internal.h"
const char chmod_usage[] = "chmod [-R] mode file [file ...]\n"
"\nmode may be an octal integer representing the bit pattern for the\n"
"\tnew mode, or a symbolic value matching the pattern\n"
"\t[ugoa]{+|-|=}[rwxst] .\n"
"\t\tu:\tUser\n"
"\t\tg:\tGroup\n"
"\t\to:\tOthers\n"
"\t\ta:\tAll\n"
"\n"
"\n+:\tAdd privilege\n"
"\n-:\tRemove privilege\n"
"\n=:\tSet privilege\n"
"\n"
"\t\tr:\tRead\n"
"\t\tw:\tWrite\n"
"\t\tx:\tExecute\n"
"\t\ts:\tSet User ID\n"
"\t\tt:\t\"Sticky\" Text\n"
"\n"
"\tModes may be concatenated, as in \"u=rwx,g=rx,o=rx,-t,-s\n"
"\n"
"\t-R:\tRecursively change the mode of all files and directories\n"
"\t\tunder the argument directory.";
int
parse_mode(
const char * s
,mode_t * or
,mode_t * and
,int * group_execute)
{
/* [ugoa]{+|-|=}[rwxstl] */
mode_t mode = 0;
mode_t groups = S_ISVTX;
char type;
char c;
do {
for ( ; ; ) {
switch ( c = *s++ ) {
case '\0':
return -1;
case 'u':
groups |= S_ISUID|S_IRWXU;
continue;
case 'g':
groups |= S_ISGID|S_IRWXG;
continue;
case 'o':
groups |= S_IRWXO;
continue;
case 'a':
groups |= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
continue;
case '+':
case '=':
case '-':
type = c;
if ( groups == S_ISVTX ) /* The default is "all" */
groups |= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
break;
default:
if ( c >= '0' && c <= '7' && mode == 0 && groups == S_ISVTX ) {
*and = 0;
*or = strtol(--s, 0, 010);
return 0;
}
else
return -1;
}
break;
}
while ( (c = *s++) != '\0' ) {
switch ( c ) {
case ',':
break;
case 'r':
mode |= S_IRUSR|S_IRGRP|S_IROTH;
continue;
case 'w':
mode |= S_IWUSR|S_IWGRP|S_IWOTH;
continue;
case 'x':
mode |= S_IXUSR|S_IXGRP|S_IXOTH;
continue;
case 's':
if ( group_execute != 0 && (groups & S_IRWXG) ) {
if ( *group_execute < 0 )
return -1;
if ( type != '-' ) {
mode |= S_IXGRP;
*group_execute = 1;
}
}
mode |= S_ISUID|S_ISGID;
continue;
case 'l':
if ( *group_execute > 0 )
return -1;
if ( type != '-' ) {
*and &= ~S_IXGRP;
*group_execute = -1;
}
mode |= S_ISGID;
groups |= S_ISGID;
continue;
case 't':
mode |= S_ISVTX;
continue;
default:
return -1;
}
break;
}
switch ( type ) {
case '=':
*and &= ~(groups);
/* fall through */
case '+':
*or |= mode & groups;
break;
case '-':
*and &= ~(mode & groups);
*or &= *and;
break;
}
} while ( c == ',' );
return 0;
}
extern int
chmod_main(struct FileInfo * i, int argc, char * * argv)
{
i->andWithMode = S_ISVTX|S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
i->orWithMode = 0;
while ( argc >= 3 ) {
if ( parse_mode(argv[1], &i->orWithMode, &i->andWithMode, 0)
== 0 ) {
argc--;
argv++;
}
else if ( strcmp(argv[1], "-R") == 0 ) {
i->recursive = 1;
argc--;
argv++;
}
else
break;
}
i->changeMode = 1;
i->complainInPostProcess = 1;
return monadic_main(i, argc, argv);
}