Factor out printf-style escape parsing logic from echo.c.

2 files changed, 9 insertions, 0 deletions

diff --git a/lib/lib.c b/lib/lib.c
index 19d28d2b..dc2de121 100644
--- a/lib/lib.c
+++ b/lib/lib.c
@@ -283,6 +283,14 @@ int stridx(char *haystack, char needle)
   return off-haystack;
 }
 
+int unescape(char c)
+{
+  char *from = "\\abefnrtv", *to = "\\\a\b\033\f\n\r\t\v";
+  int idx = stridx(from, c);
+
+  return (idx == -1) ? 0 : to[idx];
+}
+
 // If *a starts with b, advance *a past it and return 1, else return 0;
 int strstart(char **a, char *b)
 {
diff --git a/lib/lib.h b/lib/lib.h
index 887c1d57..49b02bb5 100644
--- a/lib/lib.h
+++ b/lib/lib.h
@@ -152,6 +152,7 @@ long atolx(char *c);
 long atolx_range(char *numstr, long low, long high);
 int numlen(long l);
 int stridx(char *haystack, char needle);
+int unescape(char c);
 int strstart(char **a, char *b);
 off_t fdlength(int fd);
 void loopfiles_rw(char **argv, int flags, int permissions, int failok,