Don't interpret an n*<Esc> as (n-1)*<Alt>-<Esc>

5 files changed, 64 insertions, 24 deletions

diff --git a/driver-csi.c b/driver-csi.c
index 1873e0d..7f6b008 100644
--- a/driver-csi.c
+++ b/driver-csi.c
@@ -708,7 +708,7 @@ free_driver (void *info)
 
 static termo_result_t
 peekkey_csi (termo_t *tk, termo_csi_t *csi,
-	size_t introlen, termo_key_t *key, int force, size_t *nbytep)
+	size_t introlen, termo_key_t *key, int flags, size_t *nbytep)
 {
 	(void) csi;
 
@@ -720,7 +720,7 @@ peekkey_csi (termo_t *tk, termo_csi_t *csi,
 	termo_result_t ret = parse_csi (tk, introlen, &csi_len, arg, &args, &cmd);
 	if (ret == TERMO_RES_AGAIN)
 	{
-		if (!force)
+		if (!(flags & PEEKKEY_FORCE))
 			return TERMO_RES_AGAIN;
 
 		(*tk->method.emit_codepoint) (tk, '[', key);
@@ -789,13 +789,13 @@ peekkey_csi (termo_t *tk, termo_csi_t *csi,
 
 static termo_result_t
 peekkey_ss3 (termo_t *tk, termo_csi_t *csi, size_t introlen,
-	termo_key_t *key, int force, size_t *nbytep)
+	termo_key_t *key, int flags, size_t *nbytep)
 {
 	(void) csi;
 
 	if (tk->buffcount < introlen + 1)
 	{
-		if (!force)
+		if (!(flags & PEEKKEY_FORCE))
 			return TERMO_RES_AGAIN;
 
 		(*tk->method.emit_codepoint) (tk, 'O', key);
@@ -847,7 +847,7 @@ peekkey_ss3 (termo_t *tk, termo_csi_t *csi, size_t introlen,
 
 static termo_result_t
 peekkey (termo_t *tk, void *info,
-	termo_key_t *key, int force, size_t *nbytep)
+	termo_key_t *key, int flags, size_t *nbytep)
 {
 	if (tk->buffcount == 0)
 		return tk->is_closed ? TERMO_RES_EOF : TERMO_RES_NONE;
@@ -857,14 +857,16 @@ peekkey (termo_t *tk, void *info,
 	// Now we're sure at least 1 byte is valid
 	unsigned char b0 = CHARAT (0);
 
+	if (b0 == 0x1b && tk->buffcount == 1)
+		return TERMO_RES_AGAIN;
 	if (b0 == 0x1b && tk->buffcount > 1 && CHARAT (1) == '[')
-		return peekkey_csi (tk, csi, 2, key, force, nbytep);
+		return peekkey_csi (tk, csi, 2, key, flags, nbytep);
 	if (b0 == 0x1b && tk->buffcount > 1 && CHARAT (1) == 'O')
-		return peekkey_ss3 (tk, csi, 2, key, force, nbytep);
+		return peekkey_ss3 (tk, csi, 2, key, flags, nbytep);
 	if (b0 == 0x8f)
-		return peekkey_ss3 (tk, csi, 1, key, force, nbytep);
+		return peekkey_ss3 (tk, csi, 1, key, flags, nbytep);
 	if (b0 == 0x9b)
-		return peekkey_csi (tk, csi, 1, key, force, nbytep);
+		return peekkey_csi (tk, csi, 1, key, flags, nbytep);
 	return TERMO_RES_NONE;
 }
 
diff --git a/driver-ti.c b/driver-ti.c
index 6ac213f..c94079f 100644
--- a/driver-ti.c
+++ b/driver-ti.c
@@ -466,7 +466,7 @@ free_driver (void *info)
 
 static termo_result_t
 peekkey (termo_t *tk, void *info,
-	termo_key_t *key, int force, size_t *nbytep)
+	termo_key_t *key, int flags, size_t *nbytep)
 {
 	termo_ti_t *ti = info;
 
@@ -512,7 +512,7 @@ peekkey (termo_t *tk, void *info,
 
 	// If p is not NULL then we hadn't walked off the end yet, so we have a
 	// partial match
-	if (p && !force)
+	if (p && !(flags & PEEKKEY_FORCE))
 		return TERMO_RES_AGAIN;
 
 	return TERMO_RES_NONE;
diff --git a/termo-internal.h b/termo-internal.h
index adf3e8f..54948b0 100644
--- a/termo-internal.h
+++ b/termo-internal.h
@@ -37,6 +37,12 @@ struct termo_driver_node
 	termo_driver_node_t *next;
 };
 
+enum peekey_flags
+{
+	PEEKKEY_FORCE        = 1 << 0,
+	PEEKKEY_ALT_PREFIXED = 1 << 1
+};
+
 struct termo
 {
 	int fd;
@@ -75,7 +81,7 @@ struct termo
 		void (*emit_codepoint) (termo_t *tk,
 			uint32_t codepoint, termo_key_t *key);
 		termo_result_t (*peekkey_simple) (termo_t *tk,
-			termo_key_t *key, int force, size_t *nbytes);
+			termo_key_t *key, int flags, size_t *nbytes);
 		termo_result_t (*peekkey_mouse) (termo_t *tk,
 			termo_key_t *key, size_t *nbytes);
 	}
diff --git a/termo.c b/termo.c
index 130ff40..704116b 100644
--- a/termo.c
+++ b/termo.c
@@ -37,7 +37,7 @@ static termo_driver_t *drivers[] =
 // Forwards for the "protected" methods
 static void emit_codepoint (termo_t *tk, uint32_t codepoint, termo_key_t *key);
 static termo_result_t peekkey_simple (termo_t *tk,
-	termo_key_t *key, int force, size_t *nbytes);
+	termo_key_t *key, int flags, size_t *nbytes);
 static termo_result_t peekkey_mouse (termo_t *tk,
 	termo_key_t *key, size_t *nbytes);
 
@@ -860,7 +860,7 @@ termo_canonicalise (termo_t *tk, termo_key_t *key)
 }
 
 static termo_result_t
-peekkey (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
+peekkey (termo_t *tk, termo_key_t *key, int flags, size_t *nbytep)
 {
 	int again = 0;
 
@@ -887,7 +887,7 @@ peekkey (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
 	termo_driver_node_t *p;
 	for (p = tk->drivers; p; p = p->next)
 	{
-		ret = (p->driver->peekkey) (tk, p->info, key, force, nbytep);
+		ret = (p->driver->peekkey) (tk, p->info, key, flags, nbytep);
 
 #ifdef DEBUG
 		fprintf (stderr, "Driver %s yields %s\n",
@@ -916,7 +916,7 @@ peekkey (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
 			return ret;
 
 		case TERMO_RES_AGAIN:
-			if (!force)
+			if (!(flags & PEEKKEY_FORCE))
 				again = 1;
 		case TERMO_RES_NONE:
 			break;
@@ -926,7 +926,7 @@ peekkey (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
 	if (again)
 		return TERMO_RES_AGAIN;
 
-	ret = peekkey_simple (tk, key, force, nbytep);
+	ret = peekkey_simple (tk, key, flags, nbytep);
 
 #ifdef DEBUG
 	fprintf (stderr, "getkey_simple(force=%d) yields %s\n",
@@ -942,7 +942,7 @@ peekkey (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
 }
 
 static termo_result_t
-peekkey_simple (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
+peekkey_simple (termo_t *tk, termo_key_t *key, int flags, size_t *nbytep)
 {
 	if (tk->buffcount == 0)
 		return tk->is_closed ? TERMO_RES_EOF : TERMO_RES_NONE;
@@ -950,12 +950,22 @@ peekkey_simple (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
 	unsigned char b0 = CHARAT (0);
 	if (b0 == 0x1b)
 	{
+		if (flags & PEEKKEY_ALT_PREFIXED)
+		{
+			// We got back here recursively, which means that no driver has
+			// returned TERMO_RES_AGAIN -> just return the Escape.  Otherwise
+			// we would interpret an indefinite number of <Esc>s as Alt+Esc.
+			(*tk->method.emit_codepoint) (tk, b0, key);
+			*nbytep = 1;
+			return TERMO_RES_KEY;
+		}
+
 		// Escape-prefixed value? Might therefore be Alt+key
 		if (tk->buffcount == 1)
 		{
 			// This might be an <Esc> press, or it may want to be part
 			// of a longer sequence
-			if (!force)
+			if (!(flags & PEEKKEY_FORCE))
 				return TERMO_RES_AGAIN;
 
 			(*tk->method.emit_codepoint) (tk, b0, key);
@@ -968,7 +978,8 @@ peekkey_simple (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
 		tk->buffcount--;
 
 		// Run the full driver
-		termo_result_t metakey_result = peekkey (tk, key, force, nbytep);
+		termo_result_t metakey_result =
+			peekkey (tk, key, flags | PEEKKEY_ALT_PREFIXED, nbytep);
 
 		tk->buffstart--;
 		tk->buffcount++;
@@ -998,7 +1009,7 @@ peekkey_simple (termo_t *tk, termo_key_t *key, int force, size_t *nbytep)
 		termo_result_t res = parse_multibyte
 			(tk, tk->buffer + tk->buffstart, tk->buffcount, &codepoint, nbytep);
 
-		if (res == TERMO_RES_AGAIN && force)
+		if (res == TERMO_RES_AGAIN && (flags & PEEKKEY_FORCE))
 		{
 			// There weren't enough bytes for a complete character but
 			// caller demands an answer.  About the best thing we can do here
@@ -1158,7 +1169,7 @@ termo_getkey (termo_t *tk, termo_key_t *key)
 
 	if (ret == TERMO_RES_AGAIN)
 		// Call peekkey() again in force mode to obtain whatever it can
-		(void) peekkey (tk, key, 1, &nbytes);
+		(void) peekkey (tk, key, PEEKKEY_FORCE, &nbytes);
 		// Don't eat it yet though
 
 	return ret;
@@ -1168,7 +1179,7 @@ termo_result_t
 termo_getkey_force (termo_t *tk, termo_key_t *key)
 {
 	size_t nbytes = 0;
-	termo_result_t ret = peekkey (tk, key, 1, &nbytes);
+	termo_result_t ret = peekkey (tk, key, PEEKKEY_FORCE, &nbytes);
 
 	if (ret == TERMO_RES_KEY)
 		eat_bytes (tk, nbytes);
diff --git a/tests/02getkey.c b/tests/02getkey.c
index 94f71c7..b36eb9e 100644
--- a/tests/02getkey.c
+++ b/tests/02getkey.c
@@ -7,7 +7,7 @@ main (int argc, char *argv[])
 	termo_t *tk;
 	termo_key_t key;
 
-	plan_tests (31);
+	plan_tests (38);
 
 	tk = termo_new_abstract ("vt100", NULL, 0);
 
@@ -86,6 +86,27 @@ main (int argc, char *argv[])
 	is_int (key.modifiers, TERMO_KEYMOD_CTRL,
 		"key.modifiers after Ctrl-Escape");
 
+	// Escape key in various amounts
+
+	termo_push_bytes (tk, "\x1b\x1b", 2);
+	is_int (termo_getkey (tk, &key), TERMO_RES_AGAIN,
+		"two Escapes don't yield anything");
+	is_int (termo_get_buffer_remaining (tk), 254,
+		"buffer free 254 after two Escapes");
+
+	termo_push_bytes (tk, "\x1b", 1);
+	is_int (termo_getkey (tk, &key), TERMO_RES_KEY,
+		"three Escapes yield Alt-Escape");
+	is_int (termo_get_buffer_remaining (tk), 255,
+		"buffer free 255 after three Escapes");
+
+	is_int (key.type, TERMO_TYPE_KEYSYM,
+		"key.type after three Escapes");
+	is_int (key.code.sym, TERMO_SYM_ESCAPE,
+		"key.code.sym after three Escapes");
+	is_int (key.modifiers, TERMO_KEYMOD_ALT,
+		"key.modifiers after three Escapes");
+
 	termo_destroy (tk);
 
 	return exit_status ();