Add -m support to mkdir(1).

utils/mkdir.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2012.
+    Copyright(C) Jonas 'Sortie' Termansen 2012, 2015.
 
     This program is free software: you can redistribute it and/or modify it
     under the terms of the GNU General Public License as published by the Free
@@ -25,14 +25,151 @@
 
 #include <errno.h>
 #include <error.h>
+#include <inttypes.h>
 #include <stddef.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 
-void CreateDirectory(const char* path, bool parents, bool verbose)
+static bool is_octal_string(const char* str)
 {
-	if ( mkdir(path, 0777) < 0 )
+	if ( !str[0] )
+		return false;
+	for ( size_t i = 0; str[i]; i++ )
+		if ( !('0' <= str[i] && str[i] <= '7') )
+			return false;
+	return true;
+}
+
+static mode_t execute_modespec(const char* str,
+                               mode_t mode,
+                               mode_t type,
+                               mode_t umask)
+{
+	if ( is_octal_string(str) )
+	{
+		errno = 0;
+		uintmax_t input = strtoumax((char*) str, NULL, 8);
+		if ( errno == ERANGE )
+			return (mode_t) -1;
+		if ( input & ~((uintmax_t) 07777) )
+			return (mode_t) -1;
+		return (mode_t) input;
+	}
+
+	size_t index = 0;
+	do
+	{
+		mode_t who_mask = 01000;
+		while ( true )
+		{
+			if ( str[index] == 'u' && (index++, true) )
+				who_mask |= 04700;
+			else if ( str[index] == 'g' && (index++, true) )
+				who_mask |= 02070;
+			else if ( str[index] == 'o' && (index++, true) )
+				who_mask |= 00007;
+			else if ( str[index] == 'a' && (index++, true) )
+				who_mask |= 06777;
+			else
+				break;
+		}
+		if ( !(who_mask & 0777) )
+			who_mask |= 06777 & ~umask;
+		do
+		{
+			char op;
+			switch ( (op = str[index++]) )
+			{
+			case '+': break;
+			case '-': break;
+			case '=': break;
+			default: return (mode_t) -1;
+			};
+			mode_t operand = 0;
+			if ( str[index] == 'u' || str[index] == 'g' || str[index] == 'o' )
+			{
+				char permcopy = str[index++];
+				switch ( permcopy )
+				{
+				case 'u': operand = mode >> 6 & 07; break;
+				case 'g': operand = mode >> 3 & 07; break;
+				case 'o': operand = mode >> 0 & 07; break;
+				default: __builtin_unreachable();
+				};
+				operand = operand << 0 | operand << 3 | operand << 6;
+				switch ( permcopy )
+				{
+				case 'u': if ( mode & 04000) operand |= 06000; break;
+				case 'g': if ( mode & 02000) operand |= 06000; break;
+				};
+				who_mask &= ~((mode_t) 01000);
+			}
+			else
+			{
+				bool unknown = false;
+				do
+				{
+					switch ( str[index] )
+					{
+					case 'r': operand |= 00444; break;
+					case 'w': operand |= 00222; break;
+					case 'x': operand |= 00111; break;
+					case 'X':
+						if ( S_ISDIR(type) || (mode & 0111) )
+							operand |= 00111;
+						break;
+					case 's': operand |= 06000; break;
+					case 't': operand |= 00000; break;
+					default: unknown = true; break;
+					}
+				} while ( !unknown && (index++, true) );
+			}
+			switch ( op )
+			{
+			case '+': mode |= (operand & who_mask); break;
+			case '-': mode &= ~(operand & who_mask); break;
+			case '=': mode = (mode & ~who_mask) | (operand & who_mask); break;
+			default: __builtin_unreachable();
+			}
+		} while ( str[index] == '+' ||
+		          str[index] == '-' ||
+		          str[index] == '=' );
+	} while ( str[index] == ',' && (index++, true) );
+	if ( str[index] )
+		return (mode_t) -1;
+	return mode;
+}
+
+static bool is_valid_modespec(const char* str)
+{
+	return execute_modespec(str, 0, 0, 0) != (mode_t) -1;
+}
+
+static void make_directory(const char* path,
+                           bool parents,
+                           bool verbose,
+                           const char* modespec,
+                           bool is_parent)
+{
+	mode_t my_umask = getumask();
+	mode_t mode = 0777;
+	if ( modespec )
+	{
+		mode = execute_modespec(modespec, 0777, S_IFDIR, my_umask);
+		if ( is_parent )
+			mode |= 0300;
+	}
+	while ( true )
+	{
+		if ( modespec )
+			umask(0);
+		else if ( is_parent && (my_umask & 0300) )
+			umask(my_umask & ~0300);
+		int ret = mkdir(path, mode);
+		if ( modespec || (is_parent && (my_umask & 0300)) )
+			umask(my_umask);
+		if ( ret < 0 )
 		{
 			if ( parents )
 			{
@@ -41,16 +178,18 @@ void CreateDirectory(const char* path, bool parents, bool verbose)
 				if ( errno == ENOENT )
 				{
 					char* path_copy = strdup(path);
+					if ( !path_copy )
+						error(1, errno, "malloc");
 					char* last_slash = strrchr(path_copy, '/');
 					if ( last_slash )
 					{
 						*last_slash = 0;
 						if ( *path_copy )
 						{
-						CreateDirectory(path_copy, parents, verbose);
+							make_directory(path_copy, parents, verbose,
+							               modespec, true);
 							free(path_copy);
-						CreateDirectory(path, parents, verbose);
+							continue;
-						return;
 						}
 					}
 					free(path_copy);
@@ -58,6 +197,8 @@ void CreateDirectory(const char* path, bool parents, bool verbose)
 			}
 			error(1, errno, "cannot create directory `%s'", path);
 		}
+		break;
+	}
 	if ( verbose )
 		fprintf(stderr, "%s: created directory `%s'\n", program_invocation_name, path);
 }
@@ -94,6 +235,8 @@ int main(int argc, char* argv[])
 	const char* argv0 = argv[0];
 	bool parents = false;
 	bool verbose = false;
+	const char* modespec = NULL;
+
 	for ( int i = 1; i < argc; i++ )
 	{
 		const char* arg = argv[i];
@@ -106,6 +249,20 @@ int main(int argc, char* argv[])
 		{
 			while ( char c = *++arg ) switch ( c )
 			{
+			case 'm':
+				if ( !*(modespec = arg + 1) )
+				{
+					if ( i + 1 == argc )
+					{
+						error(0, 0, "option requires an argument -- 'm'");
+						fprintf(stderr, "Try `%s --help' for more information.\n", argv[0]);
+						exit(125);
+					}
+					modespec = argv[i+1];
+					argv[++i] = NULL;
+				}
+				arg = "m";
+				break;
 			case 'p': parents = true; break;
 			case 'v': verbose = true; break;
 			default:
@@ -114,6 +271,19 @@ int main(int argc, char* argv[])
 				exit(1);
 			}
 		}
+		else if ( !strncmp(arg, "--modespec=", strlen("--modespec=")) )
+			modespec = arg + strlen("--modespec=");
+		else if ( !strcmp(arg, "--modespec") )
+		{
+			if ( i + 1 == argc )
+			{
+				error(0, 0, "option '--modespec' requires an argument");
+				fprintf(stderr, "Try `%s --help' for more information.\n", argv[0]);
+				exit(125);
+			}
+			modespec = argv[i+1];
+			argv[++i] = NULL;
+		}
 		else if ( !strcmp(arg, "--parents") )
 			parents = true;
 		else if ( !strcmp(arg, "--verbose") )
@@ -135,12 +305,16 @@ int main(int argc, char* argv[])
 	if ( argc < 2 )
 		error(1, 0, "missing operand");
 
+	if ( modespec && !is_valid_modespec(modespec) )
+		error(1, 0, "invalid mode: `%s'", modespec);
+
 	for ( int i = 1; i < argc; i++ )
 	{
 		const char* arg = argv[i];
 		if ( !arg )
 			continue;
-		CreateDirectory(arg, parents, verbose);
+		make_directory(arg, parents, verbose, modespec, false);
 	}
+
 	return 0;
 }