Scan messages for URLs

1 files changed, 96 insertions, 0 deletions

diff --git a/url.c b/url.c
new file mode 100644
index 0000000..7790461
--- /dev/null
+++ b/url.c
@@ -0,0 +1,96 @@
+/* Copyright (C) 2020  C. McEnroe <june@causal.agency>
+ *
+ * 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 <https://www.gnu.org/licenses/>.
+ */
+
+#include <err.h>
+#include <regex.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+
+#include "chat.h"
+
+static const char *Pattern = {
+	"("
+	"cvs|"
+	"ftp|"
+	"git|"
+	"gopher|"
+	"http|"
+	"https|"
+	"irc|"
+	"ircs|"
+	"magnet|"
+	"sftp|"
+	"ssh|"
+	"svn|"
+	"telnet|"
+	"vnc"
+	")"
+	":[^[:space:]>\"]+"
+};
+static regex_t Regex;
+
+static void compile(void) {
+	static bool compiled;
+	if (compiled) return;
+	compiled = true;
+	int error = regcomp(&Regex, Pattern, REG_EXTENDED);
+	if (!error) return;
+	char buf[256];
+	regerror(error, &Regex, buf, sizeof(buf));
+	errx(EX_SOFTWARE, "regcomp: %s: %s", buf, Pattern);
+}
+
+enum { Cap = 32 };
+static struct {
+	size_t ids[Cap];
+	char *nicks[Cap];
+	char *urls[Cap];
+	size_t len;
+} ring;
+
+static void push(size_t id, const char *nick, const char *url, size_t len) {
+	size_t i = ring.len++ % Cap;
+	free(ring.nicks[i]);
+	free(ring.urls[i]);
+	ring.ids[i] = id;
+	ring.nicks[i] = NULL;
+	if (nick) {
+		ring.nicks[i] = strdup(nick);
+		if (!ring.nicks[i]) err(EX_OSERR, "strdup");
+	}
+	ring.urls[i] = strndup(url, len);
+	if (!ring.urls[i]) err(EX_OSERR, "strndup");
+}
+
+void urlScan(size_t id, const char *nick, const char *mesg) {
+	if (!mesg) return;
+	compile();
+	regmatch_t match = {0};
+	for (const char *ptr = mesg; *ptr; ptr += match.rm_eo) {
+		if (regexec(&Regex, ptr, 1, &match, 0)) break;
+		push(id, nick, &ptr[match.rm_so], match.rm_eo - match.rm_so);
+	}
+}
+
+void urlOpenCount(size_t id, size_t count) {
+	// TODO
+}
+
+void urlOpenMatch(size_t id, const char *str) {
+	// TODO
+}