Import initial implementation for grep

src/grep.c

@@ -0,0 +1,157 @@
+/* $Id$ */
+/* Copyright (c) 2017 Pierre Pronchery <khorben@defora.org> */
+/* This file is part of DeforaOS Unix utils */
+/* 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
+ * the Free Software Foundation, version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>. */
+
+
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <regex.h>
+#include <errno.h>
+
+#ifndef PROGNAME
+# define PROGNAME	"grep"
+#endif
+
+
+/* grep */
+/* private */
+/* prototypes */
+static int _grep(int flags, char const * pattern, int filec, char * filev[]);
+
+static int _usage(void);
+
+
+/* functions */
+/* grep */
+static int _grep_error(char const * message, int ret);
+static int _grep_files(regex_t * reg, int filec, char * filev[]);
+static int _grep_stream(regex_t * reg, FILE * fp, char const * filename);
+
+static int _grep(int flags, char const * pattern, int filec, char * filev[])
+{
+	int ret;
+	regex_t reg;
+	int e;
+	char buf[128];
+	int n;
+
+	if((e = regcomp(&reg, pattern, flags)) != 0)
+	{
+		n = snprintf(buf, sizeof(buf), "%s: ", pattern);
+		if(n >= 0 && (unsigned)n < sizeof(buf))
+			regerror(e, &reg, &buf[n], sizeof(buf) - n);
+		else
+			regerror(e, &reg, buf, sizeof(buf));
+		return _grep_error(buf, 2);
+	}
+	if(filec == 0)
+		ret = _grep_stream(&reg, stdin, NULL);
+	else
+		ret = _grep_files(&reg, filec, filev);
+	regfree(&reg);
+	return ret;
+}
+
+static int _grep_error(char const * message, int ret)
+{
+	fprintf(stderr, "%s: %s\n", PROGNAME, message);
+	return ret;
+}
+
+static int _grep_files(regex_t * reg, int filec, char * filev[])
+{
+	int ret = 1;
+	int i;
+	FILE * fp;
+	char buf[128];
+
+	for(i = 0; i < filec; i++)
+	{
+		if((fp = fopen(filev[i], "r")) == NULL)
+		{
+			snprintf(buf, sizeof(buf), "%s: %s", filev[i],
+					strerror(errno));
+			ret = _grep_error(buf, 2);
+			continue;
+		}
+		if(_grep_stream(reg, fp, (filec > 1) ? filev[i] : NULL) == 0
+				&& ret == 1)
+			ret = 0;
+		if(fclose(fp) != 0)
+		{
+			snprintf(buf, sizeof(buf), "%s: %s", filev[i],
+					strerror(errno));
+			ret = _grep_error(buf, 2);
+		}
+	}
+	return ret;
+}
+
+static int _grep_stream(regex_t * reg, FILE * fp, char const * filename)
+{
+	int ret = 1;
+	char buf[BUFSIZ];
+	regmatch_t match;
+	int e;
+
+	while(fgets(buf, sizeof(buf), fp) != NULL)
+		if((e = regexec(reg, buf, 1, &match, 0)) == 0)
+		{
+			if(filename != NULL)
+				printf("%s:", filename);
+			printf("%s", buf);
+			if(ret == 1)
+				ret = 0;
+		}
+		else if(e != REG_NOMATCH)
+		{
+			regerror(e, reg, buf, sizeof(buf));
+			ret = -_grep_error(buf, 1);
+		}
+	return ret;
+}
+
+
+/* usage */
+static int _usage(void)
+{
+	fputs("Usage: " PROGNAME " [-i][file...]\n", stderr);
+	return 1;
+}
+
+
+/* public */
+/* functions */
+/* main */
+int main(int argc, char * argv[])
+{
+	int o;
+	int flags = 0;
+
+	while((o = getopt(argc, argv, "i")) != -1)
+		switch(o)
+		{
+			case 'i':
+				flags |= REG_ICASE;
+				break;
+			default:
+				return _usage();
+		}
+	if(optind == argc)
+		return _usage();
+	return _grep(flags, argv[optind], argc - optind - 1, &argv[optind + 1]);
+}

src/project.conf

@@ -1,4 +1,4 @@
-targets=basename,cat,chgrp,chmod,chown,cksum,cmp,cp,date,df,dirname,du,echo,false,file,find,head,id,kill,link,ln,locale,logname,ls,mkdir,mkfifo,more,mv,nice,pr,printf,ps,pwd,renice,rm,rmdir,sleep,strings,tail,test,time,touch,true,tty,uname,uniq,unlink,wc,who
+targets=basename,cat,chgrp,chmod,chown,cksum,cmp,cp,date,df,dirname,du,echo,false,file,find,grep,head,id,kill,link,ln,locale,logname,ls,mkdir,mkfifo,more,mv,nice,pr,printf,ps,pwd,renice,rm,rmdir,sleep,strings,tail,test,time,touch,true,tty,uname,uniq,unlink,wc,who
 cflags=-W -Wall -g -O2 -pedantic -fPIE -D_FORTIFY_SOURCE=2 -fstack-protector-all
 ldflags=-pie -Wl,-z,relro -Wl,-z,now
 dist=Makefile,common.c
@@ -87,6 +87,11 @@ type=binary
 sources=find.c
 install=$(BINDIR)
 
+[grep]
+type=binary
+sources=grep.c
+install=$(BINDIR)
+
 [head]
 type=binary
 sources=head.c