Try to append executable suffixes if not having extension on OS/2

Build.sh

@@ -833,6 +833,7 @@ OpenBSD)
 OS/2)
 	: ${CC=gcc}
 	: ${SIZE=echo ignore size}
+	SRCS="$SRCS os2.c"
 	;;
 OSF1)
 	HAVE_SIG_T=0	# incompatible

exec.c

@@ -1239,6 +1239,13 @@ search_access(const char *fn, int mode)
 	return (0);
 }
 
+#ifdef __OS2__
+/* check if path is something we want to find, adding executable extensions */
+#define search_access(fn, mode)	access_ex((search_access), (fn), (mode))
+#else
+#define search_access(fn, mode)	(search_access)((fn), (mode))
+#endif
+
 /*
  * search for command with PATH
  */
@@ -1260,7 +1267,11 @@ search_path(const char *name, const char *lpath,
  search_path_ok:
 			if (errnop)
 				*errnop = 0;
-			return (name);
+#ifndef __OS2__
+			return name;
+#else
+			return real_exec_name(name);
+#endif
 		}
 		goto search_path_err;
 	}

os2.c

@@ -0,0 +1,134 @@
+/*-
+ * Copyright (c) 2015
+ *	KO Myung-Hun <komh@chollian.net>
+ *
+ * Provided that these terms and disclaimer and all copyright notices
+ * are retained or reproduced in an accompanying document, permission
+ * is granted to deal in this work without restriction, including un-
+ * limited rights to use, publicly perform, distribute, sell, modify,
+ * merge, give away, or sublicence.
+ *
+ * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
+ * the utmost extent permitted by applicable law, neither express nor
+ * implied; without malicious intent or gross negligence. In no event
+ * may a licensor, author or contributor be held liable for indirect,
+ * direct, other damage, loss, or other issues arising in any way out
+ * of dealing in the work, even if advised of the possibility of such
+ * damage or existence of a defect, except proven that it results out
+ * of said person's immediate fault when using the work as intended.
+ */
+
+#include "sh.h"
+
+static char *remove_trailing_dots(char *);
+static int access_stat_ex(int (*)(), const char *, void *);
+static int test_exec_exist(const char *, char *);
+
+/* Remove trailing dots. */
+static char *
+remove_trailing_dots(char *name)
+{
+	char *p;
+
+	for (p = name + strlen(name); --p > name && *p == '.'; )
+		/* nothing */;
+
+	if (*p != '.' && *p != '/' && *p != '\\' && *p != ':')
+		p[1] = '\0';
+
+	return name;
+}
+
+#define REMOVE_TRAILING_DOTS(name)	\
+	remove_trailing_dots(strcpy(alloca(strlen(name) + 1), name))
+
+/* Alias of stat() */
+int _std_stat(const char *, struct stat *);
+
+/* Replacement for stat() of kLIBC which fails if there are trailing dots */
+int
+stat(const char *name, struct stat *buffer)
+{
+	return _std_stat(REMOVE_TRAILING_DOTS(name), buffer);
+}
+
+/* Alias of access() */
+int _std_access(const char *, int);
+
+/* Replacement for access() of kLIBC which fails if there are trailing dots */
+int
+access(const char *name, int mode)
+{
+	/*
+	 * On OS/2 kLIBC, X_OK is set only for executable files. This prevent
+	 * scripts from being executed.
+	 */
+	if (mode & X_OK)
+		mode = (mode & ~X_OK) | R_OK;
+
+	return _std_access(REMOVE_TRAILING_DOTS(name), mode);
+}
+
+#define MAX_X_SUFFIX_LEN	4
+
+static const char *x_suffix_list[] =
+	{"", ".ksh", ".exe", ".sh", ".cmd", ".com", ".bat", NULL};
+
+/* Call fn() by appending executable extensions. */
+static int
+access_stat_ex(int (*fn)(), const char *name, void *arg)
+{
+	char *x_name;
+	const char **x_suffix;
+	int rc = -1;
+
+	/* Have an extension ? */
+	if (_getext(name))
+		return fn(name, arg);
+
+	/* Otherwise, try to append executable suffixes */
+	x_name = alloc(strlen(name) + MAX_X_SUFFIX_LEN + 1, ATEMP);
+
+	for (x_suffix = x_suffix_list; rc && *x_suffix; x_suffix++) {
+		strcpy(x_name, name);
+		strcat(x_name, *x_suffix);
+
+		rc = fn(x_name, arg);
+	}
+
+	afree(x_name, ATEMP);
+
+	return rc;
+}
+
+/* access()/search_access() version */
+int
+access_ex(int (*fn)(const char *, int), const char *name, int mode)
+{
+	return access_stat_ex(fn, name, (void *)mode);
+}
+
+static int
+test_exec_exist(const char *name, char *real_name)
+{
+	struct stat sb;
+
+	if (stat(name, &sb) < 0 || !S_ISREG(sb.st_mode))
+		return -1;
+
+	strcpy(real_name, name);
+
+	return 0;
+}
+
+const char *
+real_exec_name(const char *name)
+{
+	char x_name[strlen(name) + MAX_X_SUFFIX_LEN + 1];
+	const char *real_name = name;
+
+	if (access_stat_ex(test_exec_exist, real_name, x_name) != -1)
+		strdupx(real_name, x_name, ATEMP);
+
+	return real_name;
+}

sh.h

@@ -1920,6 +1920,11 @@ char *strdup_i(const char *, Area *);
 char *strndup_i(const char *, size_t, Area *);
 #endif
 int unbksl(bool, int (*)(void), void (*)(int));
+#ifdef __OS2__
+/* os2.c */
+int access_ex(int (*)(const char *, int), const char *, int);
+const char *real_exec_name(const char *);
+#endif
 /* shf.c */
 struct shf *shf_open(const char *, int, int, int);
 struct shf *shf_fdopen(int, int, struct shf *);