ongrep

commit adbad1fc4007a72b179d2f6f9bf3bccfdbb993f6
parent 3d597962ad880110f68260c37310b9609dec5bea
Author: Stephen Gregoratto <dev@sgregoratto.me>
Date:   Sun, 14 Jun 2020 21:19:25 +1000

Replace all error reporting with the err(3) family

Diffstat:
M
ngrep.c
 | 
43
+++++++++++++++++++++++--------------------

1 file changed, 23 insertions(+), 20 deletions(-)
diff --git a/ngrep.c b/ngrep.c
@@ -24,6 +24,7 @@
 #include <arpa/inet.h>
 
 #include <ctype.h>
+#include <err.h>
 #include <errno.h>
 #include <pcap.h>
 #include <pcre.h>
@@ -117,7 +118,7 @@ main(int argc, char **argv)
 				dump_func = &dump_unwrapped;
 				dump_single = 1;
 			} else {
-				printf("fatal: unknown wrap method '%s'\n", optarg);
+				warnx("invalid wrap method: %s", optarg);
 				usage();
 			}
 			break;
@@ -217,7 +218,7 @@ main(int argc, char **argv)
 	}
 
 	if (show_hex && dump_func != &dump_formatted) {
-		printf("fatal: -x (hex dump) is incompatible with -W (alternate format)\n");
+		warnx("-x is incompatible with -W");
 		usage();
 	}
 	if (argv[optind])
@@ -235,7 +236,7 @@ main(int argc, char **argv)
 			filter = NULL;
 		}
 		if (setup_bpf_filter(argv)) {
-			pcap_perror(pd, "pcap");
+			warnx("pcap: %s", pcap_geterr(pd));
 			clean_exit(2);
 		}
 	}
@@ -262,7 +263,7 @@ main(int argc, char **argv)
 	if (dump_file) {
 		pd_dump = pcap_dump_open(pd, dump_file);
 		if (!pd_dump) {
-			fprintf(stderr, "fatal: %s\n", pcap_geterr(pd));
+			warnx("pcap_dump_open: %s", pcap_geterr(pd));
 			clean_exit(2);
 		} else
 			printf("output: %s\n", dump_file);
@@ -284,33 +285,34 @@ setup_pcap_source(void)
 {
 	if (read_file) {
 		if (!(pd = pcap_open_offline(read_file, pc_err))) {
-			perror(pc_err);
+			warnx("pcap_open_offline: %s", pc_err);
 			return 1;
 		}
 		live_read = 0;
 		printf("input: %s\n", read_file);
 	} else {
-		char *dev = usedev ? usedev : pcap_lookupdev(pc_err);
+		char *dev;
 
-		if (!dev) {
-			perror(pc_err);
+		if (usedev != NULL) {
+			dev = usedev;
+		} else if ((dev = pcap_lookupdev(pc_err)) == NULL) {
+			warnx("pcap_lookupdev: %s", pc_err);
 			return 1;
 		}
 		if ((pd = pcap_open_live(dev, snaplen, promisc, to, pc_err)) == NULL) {
-			perror(pc_err);
+			warnx("pcap_open_live: %s", pc_err);
 			return 1;
 		}
 		if (pcap_lookupnet(dev, &net.s_addr, &mask.s_addr, pc_err) == -1) {
-			perror(pc_err);
+			warnx("pcap_lookupnet: %s", pc_err);
 			memset(&net, 0, sizeof(net));
 			memset(&mask, 0, sizeof(mask));
 		}
 		if (quiet < 2) {
 			printf("interface: %s", dev);
-			if (net.s_addr && mask.s_addr) {
-				printf(" (%s/", inet_ntoa(net));
-				printf("%s)", inet_ntoa(mask));
-			}
+			if (net.s_addr && mask.s_addr)
+				printf(" (%s/%s)",
+				       inet_ntoa(net), inet_ntoa(mask));
 			printf("\n");
 		}
 	}
@@ -348,7 +350,8 @@ setup_pcap_source(void)
 		link_offset = PFLOGHDR_SIZE;
 		break;
 	default:
-		fprintf(stderr, "fatal: unsupported interface type %u\n", pcap_datalink(pd));
+		warnx("fatal: unsupported interface type %u",
+		      pcap_datalink(pd));
 		return 1;
 	}
 
@@ -363,7 +366,7 @@ setup_bpf_filter(char **argv)
 		FILE *f = fopen(filter_file, "r");
 
 		if (!f || !fgets(buf, sizeof(buf) - 1, f)) {
-			fprintf(stderr, "fatal: unable to get filter from %s: %s\n", filter_file, strerror(errno));
+			warn("cannot read filter from %s", filter_file);
 			usage();
 		}
 		fclose(f);
@@ -406,12 +409,12 @@ setup_matcher(void)
 		char *s, *d;
 
 		if (re_match_word || re_ignore_case) {
-			fprintf(stderr, "fatal: regex switches are incompatible with binary matching\n");
+			warn("fatal: regex switches are incompatible with binary matching");
 			return 1;
 		}
 		len = (uint32_t) strlen(match_data);
 		if (len % 2 != 0 || !strishex(match_data)) {
-			fprintf(stderr, "fatal: invalid hex string specified\n");
+			warnx("fatal: invalid hex string specified");
 			return 1;
 		}
 		bin_data = (char *) malloc(len / 2);
@@ -449,7 +452,7 @@ setup_matcher(void)
 		pattern = pcre_compile(match_data, pcre_options, (const char **) &re_err, &err_offset, 0);
 
 		if (!pattern) {
-			fprintf(stderr, "compile failed: %s\n", re_err);
+			warnx("pcre_compile: %s", re_err);
 			return 1;
 		}
 		pattern_extra = pcre_study(pattern, 0, (const char **) &re_err);
@@ -755,7 +758,7 @@ re_match_func(unsigned char *data, uint32_t len, uint16_t *mindex,
 		case PCRE_ERROR_BADMAGIC:
 		case PCRE_ERROR_UNKNOWN_NODE:
 		case PCRE_ERROR_NOMEMORY:
-			perror("she's dead, jim\n");
+			warnx("pcre_exec: fatal error");
 			clean_exit(2);
 		case PCRE_ERROR_NOMATCH:
 			return 0;