allow some two-char c string escape codesHEADmaster

\a, \b, \f, \n, \r, \t, \v

2 files changed, 38 insertions, 3 deletions

diff --git a/doc/interface.md b/doc/interface.md
index 978ecb3..0882acd 100644
--- a/doc/interface.md
+++ b/doc/interface.md
@@ -115,8 +115,9 @@ floating point number that can be read by the standard library `strtod`
 function and stored in a `double` type. this includes arguments like "4.9",
 "-1.2e20", "infinity", or "nan".
 
-arguments acceptable to type `SIMPLE_OPT_CHAR` may be any single-byte
-character.
+arguments acceptable to type `SIMPLE_OPT_CHAR` may be any single-byte character
+or one of the following two-character escape sequences: `\a`, `\b`, `\f`, `\n`,
+`\r`, `\t`, `\v`.
 
 arguments acceptable to type `SIMPLE_OPT_STRING` may be any string of
 characters the user passes.
diff --git a/simple-opt.h b/simple-opt.h
index d85ee3d..b298975 100644
--- a/simple-opt.h
+++ b/simple-opt.h
@@ -195,8 +195,42 @@ strmatch_out:
 		return true;
 
 	case SIMPLE_OPT_CHAR:
-		if (strlen(s) != 1)
+		if (strlen(s) == 2 && s[0] == '\\') {
+			switch (s[1]) {
+			case '0':
+				o->val.v_char = '\0';
+				break;
+			case 'a':
+				o->val.v_char = '\a';
+				break;
+			case 'b':
+				o->val.v_char = '\b';
+				break;
+			case 't':
+				o->val.v_char = '\t';
+				break;
+			case 'n':
+				o->val.v_char = '\n';
+				break;
+			case 'v':
+				o->val.v_char = '\v';
+				break;
+			case 'f':
+				o->val.v_char = '\f';
+				break;
+			case 'r':
+				o->val.v_char = '\r';
+				break;
+			case '\\':
+				o->val.v_char = '\\';
+				break;
+			default:
+				return false;
+			}
+			return true;
+		} else if (strlen(s) != 1) {
 			return false;
+		}
 
 		o->val.v_char = s[0];
 		return true;