Port path.getabsolute() from Lua to C

src/base/path.lua

@@ -32,51 +32,6 @@
 	end
 
 
---
--- Get the absolute file path from a relative path. The requested
--- file path doesn't actually need to exist.
---
-
-	function path.getabsolute(p)
-		if type(p) == "table" then
-			local result = {}
-			for _, value in ipairs(p) do
-				table.insert(result, path.getabsolute(value))
-			end
-			return result
-		end
-
-		-- normalize the target path
-		p = path.translate(p, "/")
-		if (p == "") then p = "." end
-
-		-- if the directory is already absolute I don't need to do anything
-		local result = iif (path.isabsolute(p), nil, os.getcwd())
-
-		-- split up the supplied relative path and tackle it bit by bit
-		for n, part in ipairs(p:explode("/", true)) do
-			if (part == "" and n == 1) then
-				result = "/"
-			elseif (part == "..") then
-				result = path.getdirectory(result)
-			elseif (part ~= ".") then
-				-- Environment variables embedded in the path need to be treated
-				-- as relative paths; path.join() makes them absolute
-				if (part:startswith("$") and n > 1) then
-					result = result .. "/" .. part
-				else
-					result = path.join(result, part)
-				end
-			end
-		end
-
-		-- if I end up with a trailing slash remove it
-		result = iif(result:endswith("/"), result:sub(1, -2), result)
-
-		return result
-	end
-
-
 --
 -- Retrieve the filename portion of a path, without any extension.
 --

src/host/os_getcwd.c

@@ -9,26 +9,32 @@
 int os_getcwd(lua_State* L)
 {
 	char buffer[0x4000];
-	char* ch;
+	if (do_getcwd(buffer, 0x4000)) {
+		lua_pushstring(L, buffer);
+		return 1;
+	}
+	else {
+		return 0;
+	}
+}
+
+
+int do_getcwd(char* buffer, size_t size)
+{
 	int result;
 
 #if PLATFORM_WINDOWS
 	result = (GetCurrentDirectory(0x4000, buffer) != 0);
+	if (result) {
+		char* ch;
+		for (ch = buffer; *ch != '\0'; ++ch)
+		{
+			if (*ch == '\\') *ch = '/';
+		}
+	}
 #else
 	result = (getcwd(buffer, 0x4000) != 0);
 #endif
 
-	if (!result)
-		return 0;
-
-	/* convert to platform-neutral directory separators */
-	for (ch = buffer; *ch != '\0'; ++ch)
-	{
-		if (*ch == '\\') *ch = '/';
-	}
-
-	lua_pushstring(L, buffer);
-	return 1;
+	return result;
 }
-
-

src/host/path_getabsolute.c

@@ -0,0 +1,92 @@
+/**
+ * \file   path_getabsolute.c
+ * \brief  Returns an absolute version of a relative path.
+ * \author Copyright (c) 2002-2013 Jason Perkins and the Premake project
+ */
+
+#include "premake.h"
+#include <string.h>
+
+
+static void getabsolute(char* result, const char* value)
+{
+	int i;
+	char* ch;
+	char buffer[0x4000] = { '\0' };
+
+	/* if the path is not already absolute, base it on working dir */
+	if (!do_isabsolute(value)) {
+		do_getcwd(buffer, 0x4000);
+		strcat(buffer, "/");
+	}
+
+	/* normalize the path */
+	strcat(buffer, value);
+	for (ch = buffer; *ch != '\0'; ++ch) {
+		if (*ch == '\\') {
+			*ch = '/';
+		}
+	}
+
+	/* process it part by part */
+	result[0] = '\0';
+	if (buffer[0] == '/') {
+		strcat(result, "/");
+	}
+
+	ch = strtok(buffer, "/");
+	while (ch) {
+		/* remove ".." */
+		if (strcmp(ch, "..") == 0) {
+			i = strlen(result) - 2;
+			while (i >= 0 && result[i] != '/') {
+				--i;
+			}
+			if (i >= 0) {
+				result[i + 1] = '\0';
+			}
+		}
+
+		/* allow everything except "." */
+		else if (strcmp(ch, ".") != 0) {
+			strcat(result, ch);
+			strcat(result, "/");
+		}
+
+		ch = strtok(NULL, "/");
+	}
+
+	/* remove trailing slash */
+	i = strlen(result) - 1;
+	if (result[i] == '/') {
+		result[i] = '\0';
+	}
+}
+
+
+int path_getabsolute(lua_State* L)
+{
+	char buffer[0x4000];
+
+	if (lua_istable(L, 1)) {
+		int i = 0;
+		lua_newtable(L);
+		lua_pushnil(L);
+		while (lua_next(L, 1)) {
+			const char* value = luaL_checkstring(L, 4);
+			getabsolute(buffer, value);
+			lua_pop(L, 1);
+
+			lua_pushnumber(L, ++i);
+			lua_pushstring(L, buffer);
+			lua_settable(L, 2);
+		}
+		return 1;
+	}
+	else {
+		const char* value = luaL_checkstring(L, 1);
+		getabsolute(buffer, value);
+		lua_pushstring(L, buffer);
+		return 1;
+	}
+}

src/host/premake.c

@@ -35,6 +35,7 @@ extern const char* builtin_scripts[];
 
 /* Built-in functions */
 static const luaL_Reg path_functions[] = {
+	{ "getabsolute", path_getabsolute },
 	{ "isabsolute",  path_isabsolute },
 	{ "join", path_join },
 	{ NULL, NULL }

src/host/premake.h

@@ -48,11 +48,13 @@
 
 /* Bootstrapping helper functions */
 unsigned long do_hash(const char* str, int seed);
+int do_getcwd(char* buffer, size_t size);
 int do_isabsolute(const char* path);
 int do_isfile(const char* filename);
 
 
 /* Built-in functions */
+int path_getabsolute(lua_State* L);
 int path_isabsolute(lua_State* L);
 int path_join(lua_State* L);
 int os_chdir(lua_State* L);

tests/base/test_path.lua

@@ -1,7 +1,7 @@
 --
 -- tests/base/test_path.lua
 -- Automated test suite for the action list.
--- Copyright (c) 2008-2010 Jason Perkins and the Premake project
+-- Copyright (c) 2008-2013 Jason Perkins and the Premake project
 --
 
 	local suite = test.declare("path")
@@ -11,41 +11,59 @@
 -- path.getabsolute() tests
 --
 
-	function suite.getabsolute_ReturnsCorrectPath_OnMissingSubdir()
-		local expected = path.translate(os.getcwd(), "/") .. "/a/b/c"
+	function suite.getabsolute_worksWithMissingSubdirs()
+		local expected = os.getcwd() .. "/a/b/c"
 		test.isequal(expected, path.getabsolute("a/b/c"))
 	end
 
-	function suite.getabsolute_RemovesDotDots_OnWindowsAbsolute()
+	function suite.getabsolute_removesDotDots_onWindows()
 		test.isequal("c:/ProjectB/bin", path.getabsolute("c:/ProjectA/../ProjectB/bin"))
 	end
 
-	function suite.getabsolute_RemovesDotDots_OnPosixAbsolute()
+	function suite.getabsolute_removesDotDots_OnPosix()
 		test.isequal("/ProjectB/bin", path.getabsolute("/ProjectA/../ProjectB/bin"))
 	end
 
-	function suite.getabsolute_OnTrailingSlash()
-		local expected = path.translate(os.getcwd(), "/") .. "/a/b/c"
-		test.isequal(expected, path.getabsolute("a/b/c/"))
+	function suite.getabsolute_limitsDotDots_onWindows()
+		test.isequal("c:/ProjectB/bin", path.getabsolute("c:/ProjectA/../../ProjectB/bin"))
 	end
 
-	function suite.getabsolute_OnLeadingEnvVar()
+	function suite.getabsolute_limitsDotDots_OnPosix()
+		test.isequal("/ProjectB/bin", path.getabsolute("/ProjectA/../../ProjectB/bin"))
+	end
+
+	function suite.getabsolute_removesDot()
+		test.isequal("/ProjectA/ProjectB/bin", path.getabsolute("/ProjectA/./ProjectB/bin"))
+	end
+
+	function suite.getabsolute_removesTrailingSlash()
+		test.isequal("/a/b/c", path.getabsolute("/a/b/c/"))
+	end
+
+	function suite.getabsolute_onLeadingEnvVar()
 		test.isequal("$(HOME)/user", path.getabsolute("$(HOME)/user"))
 	end
 
-	function suite.getabsolute_OnMultipleEnvVar()
+	function suite.getabsolute_onMultipleEnvVar()
 		test.isequal("$(HOME)/$(USER)", path.getabsolute("$(HOME)/$(USER)"))
 	end
 
-	function suite.getabsolute_OnTrailingEnvVar()
-		local expected = path.translate(os.getcwd(), "/") .. "/home/$(USER)"
-		test.isequal(expected, path.getabsolute("home/$(USER)"))
+	function suite.getabsolute_onTrailingEnvVar()
+		test.isequal("/home/$(USER)", path.getabsolute("/home/$(USER)"))
 	end
 
-	function suite.getabsolute_OnLeadingEnvVarQuoted()
+	function suite.getabsolute_onLeadingEnvVarQuoted()
 		test.isequal('"$(HOME)/user"', path.getabsolute('"$(HOME)/user"'))
 	end
 
+	function suite.getabsolute_normalizesPaths()
+		test.isequal("c:/ProjectB/bin", path.getabsolute("c:\\ProjectB\\bin"))
+	end
+
+	function suite.getabsolute_acceptsTables()
+		test.isequal({ "/a/b", "/c/d" }, path.getabsolute({ "/a/b", "/c/d" }))
+	end
+
 
 --
 -- path.getbasename() tests