Support basic escape ASCII escape sequences

1 files changed, 18 insertions, 0 deletions

diff --git a/grab.c b/grab.c
index d7f1f50..272fe3c 100644
--- a/grab.c
+++ b/grab.c
@@ -69,6 +69,7 @@ static char *xstrchrnul(const char *, char);
 
 static char delim = '\n';
 static int rv = EXIT_SUCCESS;
+
 static const cmd_func op_table[UCHAR_MAX] = {
 	['g'] = cmdg,
 	['v'] = cmdg,
@@ -76,6 +77,11 @@ static const cmd_func op_table[UCHAR_MAX] = {
 	['y'] = cmdy,
 };
 
+static const char esc_table[UCHAR_MAX] = {
+	['\\'] = '\\', ['a'] = '\a', ['b'] = '\b', ['f'] = '\f',
+	['n'] = '\n',  ['r'] = '\r', ['t'] = '\t', ['v'] = '\v',
+};
+
 static void
 usage(const char *s)
 {
@@ -319,6 +325,18 @@ mkregex(char *s, size_t n)
 	int ret;
 	regex_t r;
 
+	for (size_t i = 0; i < n - 1; i++) {
+		if (s[i] == '\\') {
+			char c = esc_table[(uchar)s[i + 1]];
+			if (c) {
+				for (size_t j = i; j < n - 1; j++)
+					s[j] = s[j + 1];
+				s[i] = c;
+				n--;
+			}
+		}
+	}
+
 	s[n] = 0;
 	if ((ret = regcomp(&r, s, REG_EXTENDED | REG_NEWLINE)) != 0) {
 		char emsg[128];