Add mes and mescc-tools-extra

mescc-tools-extra contains two important tools:
- cp
- chmod

mes first builds itself from a mes 0.21 seed as used by guix, and then
builds a mes 0.22 and then mes 0.22 using that created mes 0.22.

It does /not/ use bootstrap.sh as we don't have a proper shell at this
point, it has been manually adapted for kaem.

sysa/mescc-tools-extra/chmod.c

@@ -0,0 +1,172 @@
+/* Copyright (C) 2020 fosslinux
+ * This file is part of mescc-tools
+ *
+ * mescc-tools 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 Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * mescc-tools is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with mescc-tools.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+/* Define all of the constants */
+// CONSTANT FALSE 0
+#define FALSE 0
+// CONSTANT TRUE 1
+#define TRUE 1
+// CONSTANT MAX_STRING 4096
+#define MAX_STRING 4096
+// CONSTANT MAX_ARRAY 256
+#define MAX_ARRAY 256
+
+/* There are all of the constants we need for the bitmask */
+			/* constant name */ /* decimal */	/* octal */
+// CONSTANT S_ISUID	 			2048			/* 04000 */
+// CONSTANT S_ISGID				1024			/* 02000 */
+// CONSTANT	S_ISVTX				 512			/* 01000 */
+// CONSTANT	S_IRUSR				 256			/* 00400 */
+// CONSTANT	S_IWUSR				 128			/* 00200 */
+// CONSTANT	S_IXUSR				  64			/* 00100 */
+// CONSTANT	S_IRGRP				  32			/* 00040 */
+// CONSTANT	S_IWGRP				  16			/* 00020 */
+// CONSTANT	S_IXGRP				   8			/* 00010 */
+// CONSTANT	S_IROTH				   4			/* 00004 */
+// CONSTANT	S_IWOTH				   2			/* 00002 */
+// CONSTANT	S_IXOTH				   1			/* 00001 */
+
+/* Prototypes for external funcs */
+void file_print(char* s, FILE* f);
+char* prepend_char(char a, char* s);
+int numerate_string(char *a);
+void require(int bool, char* error);
+char* copy_string(char* target, char* source);
+int match(char* a, char* b);
+/* Globals */
+int verbose;
+
+/* UTILITY FUNCTIONS */
+
+/* Function to find the length of a char**; an array of strings */
+int array_length(char** array)
+{
+	int length = 0;
+	while(array[length] != NULL)
+	{
+		length = length + 1;
+	}
+	return length;
+}
+
+/* PROCESSING FUNCTIONS */
+
+int main(int argc, char** argv)
+{
+	/* Initialize variables */
+	char** files = calloc(MAX_ARRAY, sizeof(char*));
+	require(files != NULL, "Memory initialization of files failed\n");
+	int files_index = 0;
+	char* mode = NULL;
+
+	/* Set defaults */
+	verbose = FALSE;
+
+	int i = 1;
+	/* Loop arguments */
+	while(i <= argc)
+	{
+		if(NULL == argv[i])
+		{ /* Ignore and continue */
+			i = i + 1;
+		}
+		else if(match(argv[i], "-h") || match(argv[i], "--help"))
+		{
+			file_print("Usage: ", stdout);
+			file_print(argv[0], stdout);
+			file_print(" [-h | --help] [-V | --version] [-v | --verbose]\n", stdout);
+			exit(EXIT_SUCCESS);
+		}
+		else if(match(argv[i], "-V") || match(argv[i], "--version"))
+		{ /* Output version */
+			file_print("chmod version 1.1.0\n", stdout);
+			exit(EXIT_SUCCESS);
+		}
+		else if(match(argv[i], "-v") || match(argv[i], "--verbose"))
+		{
+			verbose = TRUE;
+			i = i + 1;
+		}
+		else if(argv[i][0] != '-')
+		{ /* It must be the file or the mode */
+			if(mode == NULL)
+			{ /* Mode always comes first */
+				mode = calloc(MAX_STRING, sizeof(char));
+				require(mode != NULL, "Memory initialization of mode failed\n");
+				copy_string(mode, argv[i]);
+			}
+			else
+			{ /* It's a file, as the mode is already done */
+				files[files_index] = calloc(MAX_STRING, sizeof(char));
+				require(files[files_index] != NULL, "Memory initialization of files[files_index] failed\n");
+				copy_string(files[files_index], argv[i]);
+				files_index = files_index + 1;
+			}
+			i = i + 1;
+		}
+		else
+		{ /* Unknown argument */
+			file_print("UNKNOWN_ARGUMENT\n", stderr);
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	/* Ensure the two values have values */
+	require(mode != NULL, "Provide a mode\n");
+	require(files[0] != NULL, "Provide a file\n");
+
+	/* Convert the mode str into octal */
+	if(mode[0] != '0')
+	{ /* We need to indicate it is octal */
+		mode = prepend_char('0', mode);
+	}
+	int omode = numerate_string(mode);
+
+	/* Loop over files to be operated on */
+	FILE* test;
+	for(i = 0; i < array_length(files); i = i + 1)
+	{
+		/* Make sure the file can be opened */
+		test = fopen(files[i], "r");
+		require(test != NULL, "A file cannot be read\n");
+		fclose(test);
+
+		/* Verbose message */
+		if(verbose)
+		{
+			file_print("mode of '", stdout);
+			file_print(files[i], stdout);
+			file_print("' changed to ", stdout);
+			file_print(mode, stdout);
+			file_print("\n", stdout);
+		}
+
+		/* Perform the chmod */
+		chmod(files[i], omode);
+
+		free(files[i]);
+	}
+
+	free(mode);
+	free(files);
+}