I had partially implemented the test/[ command a while ago, and then got
distracted with other things and never came back to it - I remembered
about it when I saw this other sbase patch.
This version has binary operators (e.g. = != -gt -lt) implemented
(limited to the r, and properly handles being called as /bin/[ (previous
version required argv[0] to be == "[" to invoke [ behavior, this one
simply checks the last character of argv[0])
It still only supports the POSIX single-test syntax, with no support for
the XSI ( ) -a -o operators.
/* See LICENSE file for copyright and license details. */
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include "util.h"
static bool unary(const char *, const char *);
static bool binary(const char *, const char *, const char *);
static void usage(void);
bool is_bracket = false;
int
main(int argc, char *argv[])
{
bool ret = false, not = false;
argv0 = argv[0];
if(*argv0 && argv0[strlen(argv0)-1] == '[') {
/* checks if argv[0] ends with [
* for [ or /bin/[ etc */
is_bracket = true;
if(strcmp(argv[argc-1], "]") != 0)
usage();
argc--;
}
if(argc > 2 && !strcmp(argv[1], "!")) {
not = true;
argv++;
argc--;
}
switch(argc) {
case 2:
ret = *argv[1] != '\0';
break;
case 3:
ret = unary(argv[1], argv[2]);
break;
case 4:
ret = binary(argv[1], argv[2], argv[3]);
break;
default:
usage();
}
if(not)
ret = !ret;
return ret ? EXIT_SUCCESS : EXIT_FAILURE;
}
bool
unary(const char *op, const char *arg)
{
struct stat st;
int r;
if(op[0] != '-' || op[1] == '\0' || op[2] != '\0')
usage();
switch(op[1]) {
case 'b': case 'c': case 'd': case 'f': case 'g':
case 'p': case 'S': case 's': case 'u':
if((r = stat(arg, &st)) == -1)
return false; /* -e */
switch(op[1]) {
case 'b':
return S_ISBLK(st.st_mode);
case 'c':
return S_ISCHR(st.st_mode);
case 'd':
return S_ISDIR(st.st_mode);
case 'f':
return S_ISREG(st.st_mode);
case 'g':
return st.st_mode & S_ISGID;
case 'p':
return S_ISFIFO(st.st_mode);
case 'S':
return S_ISSOCK(st.st_mode);
case 's':
return st.st_size > 0;
case 'u':
return st.st_mode & S_ISUID;
}
case 'e':
return access(arg, F_OK) == 0;
case 'r':
return access(arg, R_OK) == 0;
case 'w':
return access(arg, W_OK) == 0;
case 'x':
return access(arg, X_OK) == 0;
case 'h': case 'L':
return lstat(arg, &st) == 0 && S_ISLNK(st.st_mode);
case 't':
return isatty((int)estrtol(arg, 0));
case 'n':
return arg[0] != '\0';
case 'z':
return arg[0] == '\0';
default:
usage();
}
return false; /* should not reach */
}
bool
binary(const char *arg1, const char *op, const char *arg2)
{
intmax_t iarg1, iarg2;
if(!strcmp(op,"=") || !strcmp(op,"==")) {
return strcmp(arg1,arg2) == 0;
}
if(!strcmp(op,"!=")) {
return strcmp(arg1,arg2) != 0;
}
/* Note: this does not handle correctly if the values are both
* out of range in the same direction, it will consider them
* equal. */
iarg1 = strtoimax(arg1, 0, 10);
iarg2 = strtoimax(arg2, 0, 10);
if(!strcmp(op,"-eq")) return iarg1 == iarg2;
if(!strcmp(op,"-ne")) return iarg1 != iarg2;
if(!strcmp(op,"-gt")) return iarg1 > iarg2;
if(!strcmp(op,"-ge")) return iarg1 >= iarg2;
if(!strcmp(op,"-lt")) return iarg1 < iarg2;
if(!strcmp(op,"-le")) return iarg1 <= iarg2;
usage();
}
void
usage(void)
{
const char *ket = is_bracket ? " ]" : "";
eprintf("usage: %s string%s\n"
" %s [!] [-bcdefghLnprSstuwxz] string%s\n"
" %s [!] string1 {=,!=} string2%s\n"
" %s [!] int1 -{eq,ne,gt,ge,lt,le} int2%s\n"
, argv0, ket, argv0, ket, argv0, ket, argv0, ket);
}
