Files
sbase/grep.c
FRIGN 0545d32ce9 Handle '-' consistently
In general, POSIX does not define /dev/std{in, out, err} because it
does not want to depend on the dev-filesystem.
For utilities, it thus introduced the '-'-keyword to denote standard
input (and output in some cases) and the programs have to deal with
it accordingly.

Sadly, the design of many tools doesn't allow strict shell-redirections
and many scripts don't even use this feature when possible.

Thus, we made the decision to implement it consistently across all
tools where it makes sense (namely those which read files).

Along the way, I spotted some behavioural bugs in libutil/crypt.c and
others where it was forgotten to fshut the files after use.
2015-05-16 13:34:00 +01:00

284 lines
5.3 KiB
C

/* See LICENSE file for copyright and license details. */
#include <regex.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include "queue.h"
#include "util.h"
enum { Match = 0, NoMatch = 1, Error = 2 };
static void addpattern(const char *, size_t);
static void addpatternfile(FILE *);
static int grep(FILE *, const char *);
static int Eflag;
static int Fflag;
static int Hflag;
static int eflag;
static int fflag;
static int hflag;
static int iflag;
static int sflag;
static int vflag;
static int wflag;
static int xflag;
static int many;
static int mode;
struct pattern {
char *pattern;
regex_t preg;
SLIST_ENTRY(pattern) entry;
};
static SLIST_HEAD(phead, pattern) phead;
static void
addpattern(const char *pattern, size_t patlen)
{
struct pattern *pnode;
char *tmp;
int bol, eol;
size_t len;
if (!patlen)
return;
/* a null BRE/ERE matches every line */
if (!Fflag)
if (pattern[0] == '\0')
pattern = ".";
if (!Fflag && xflag) {
tmp = enmalloc(Error, patlen + 3);
snprintf(tmp, patlen + 3, "%s%s%s",
pattern[0] == '^' ? "" : "^",
pattern,
pattern[patlen - 1] == '$' ? "" : "$");
} else if (!Fflag && wflag) {
len = patlen + 5 + (Eflag ? 2 : 4);
tmp = enmalloc(Error, len);
bol = eol = 0;
if (pattern[0] == '^')
bol = 1;
if (pattern[patlen - 1] == '$')
eol = 1;
snprintf(tmp, len, "%s\\<%s%.*s%s\\>%s",
bol ? "^" : "",
Eflag ? "(" : "\\(",
(int)patlen - bol - eol, pattern + bol,
Eflag ? ")" : "\\)",
eol ? "$" : "");
} else {
tmp = enstrdup(Error, pattern);
}
pnode = enmalloc(Error, sizeof(*pnode));
pnode->pattern = tmp;
SLIST_INSERT_HEAD(&phead, pnode, entry);
}
static void
addpatternfile(FILE *fp)
{
static char *buf = NULL;
static size_t size = 0;
ssize_t len = 0;
while ((len = getline(&buf, &size, fp)) > 0) {
if (len > 0 && buf[len - 1] == '\n')
buf[len - 1] = '\0';
addpattern(buf, (size_t)len);
}
if (ferror(fp))
enprintf(Error, "read error:");
}
static int
grep(FILE *fp, const char *str)
{
static char *buf = NULL;
static size_t size = 0;
ssize_t len = 0;
long c = 0, n;
struct pattern *pnode;
int match = NoMatch;
for (n = 1; (len = getline(&buf, &size, fp)) > 0; n++) {
/* Remove the trailing newline if one is present. */
if (len && buf[len - 1] == '\n')
buf[len - 1] = '\0';
SLIST_FOREACH(pnode, &phead, entry) {
if (!Fflag) {
if (regexec(&pnode->preg, buf[0] == '\0' ? "\n" : buf, 0, NULL, 0) ^ vflag)
continue;
} else {
if (!xflag) {
if ((iflag ? strcasestr : strstr)(buf, pnode->pattern))
match = Match;
else
match = NoMatch;
} else {
if (!(iflag ? strcasecmp : strcmp)(buf, pnode->pattern))
match = Match;
else
match = NoMatch;
}
if (match ^ vflag)
continue;
}
switch (mode) {
case 'c':
c++;
break;
case 'l':
puts(str);
goto end;
case 'q':
exit(Match);
default:
if (!hflag && (many || Hflag))
printf("%s:", str);
if (mode == 'n')
printf("%ld:", n);
puts(buf);
break;
}
match = Match;
break;
}
}
if (mode == 'c')
printf("%ld\n", c);
end:
if (ferror(fp)) {
weprintf("%s: read error:", str);
match = Error;
}
return match;
}
static void
usage(void)
{
enprintf(Error, "usage: %s [-EFHchilnqsvwx] [-e pattern] [-f file] [pattern] [file ...]\n", argv0);
}
int
main(int argc, char *argv[])
{
struct pattern *pnode;
int i, m, flags = REG_NOSUB, match = NoMatch;
FILE *fp;
char *arg;
SLIST_INIT(&phead);
ARGBEGIN {
case 'E':
Eflag = 1;
flags |= REG_EXTENDED;
break;
case 'F':
Fflag = 1;
break;
case 'H':
Hflag = 1;
hflag = 0;
break;
case 'e':
arg = EARGF(usage());
if (!(fp = fmemopen(arg, strlen(arg) + 1, "r")))
eprintf("fmemopen:");
addpatternfile(fp);
efshut(fp, arg);
eflag = 1;
break;
case 'f':
arg = EARGF(usage());
fp = fopen(arg, "r");
if (!fp)
enprintf(Error, "fopen %s:", arg);
addpatternfile(fp);
efshut(fp, arg);
fflag = 1;
break;
case 'h':
hflag = 1;
Hflag = 0;
break;
case 'c':
case 'l':
case 'n':
case 'q':
mode = ARGC();
break;
case 'i':
flags |= REG_ICASE;
iflag = 1;
break;
case 's':
sflag = 1;
break;
case 'v':
vflag = 1;
break;
case 'w':
wflag = 1;
break;
case 'x':
xflag = 1;
break;
default:
usage();
} ARGEND;
if (argc == 0 && !eflag && !fflag)
usage(); /* no pattern */
/* just add literal pattern to list */
if (!eflag && !fflag) {
if (!(fp = fmemopen(argv[0], strlen(argv[0]) + 1, "r")))
eprintf("fmemopen:");
addpatternfile(fp);
efshut(fp, argv[0]);
argc--;
argv++;
}
if (!Fflag)
/* Compile regex for all search patterns */
SLIST_FOREACH(pnode, &phead, entry)
enregcomp(Error, &pnode->preg, pnode->pattern, flags);
many = (argc > 1);
if (argc == 0) {
match = grep(stdin, "<stdin>");
} else {
for (; *argv; argc--, argv++) {
if ((*argv)[0] == '-' && !(*argv)[1]) {
*argv = "<stdin>";
fp = stdin;
} else if (!(fp = fopen(*argv, "r"))) {
if (!sflag)
weprintf("fopen %s:", *argv);
match = Error;
continue;
}
m = grep(fp, *argv);
if (m == Error || (match != Error && m == Match))
match = m;
if (fp != stdin && fshut(fp, *argv))
match = Error;
}
}
enfshut(Error, stdin, "<stdin>");
enfshut(Error, stdout, "<stdout>");
return match;
}