sbase/grep.c
FRIGN 9a074144c9 Remove handrolled strcmp()'s
Favor readability over bare-metal.
2015-05-21 15:43:38 +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 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 (!strcmp(*argv, "-")) {
*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;
}