Release v0.0.0.1

Can't stress enough that this isn't ready for production.

Makefile

@@ -0,0 +1,16 @@
+components = fssb.o \
+			 arguments.o \
+			 utils.o \
+			 proxyfile.o
+
+all: $(components)
+	cc -o fssb $(components) -lcrypto
+
+fssb.o: fssb.c
+arguments.o: arguments.c
+utils.o: utils.c
+proxyfile.o: proxyfile.c
+
+clean:
+	rm -rf *.o
+	rm -rf fssb

arguments.c

@@ -0,0 +1,214 @@
+/**
+ * arguments.h - Argument handling.  Part of the FSSB project.
+ *
+ * Copyright (C) 2016 Adhityaa Chandrasekar
+ *
+ * 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 Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "arguments.h"
+
+#define INIT_HELP_ALLOC 8
+
+/**
+ * insert_help - inserts a line of help into the list
+ * @arg:  the argument
+ * @desc: help text that's supposed to accompany the argument
+ */
+void insert_help(char *arg, char *desc, int num_vals) {
+    if(help_list_count >= help_list_allocated) {
+        help_list_allocated *= 2;
+        help_list = (help *)realloc(help_list, help_list_allocated);
+    }
+    strcpy(help_list[help_list_count].arg, arg);
+    strcpy(help_list[help_list_count].desc, desc);
+    help_list[help_list_count].num_vals = num_vals;
+    help_list_count++;
+}
+
+/**
+ * build_help - builds the list of arguments and descriptions.
+ */
+void build_help() {
+    help_list_count = 0;
+
+    help_list = (help *)malloc(sizeof(help)*INIT_HELP_ALLOC);
+    help_list_allocated = INIT_HELP_ALLOC;
+
+    insert_help("-h", "show this help and exit", 0);
+    insert_help("-r", "remove all temporary files at the end", 0);
+    insert_help("-o", "logging output file", 1);
+    insert_help("-m", "print file to proxyfile map at the end", 0);
+}
+
+/**
+ * check_args_validity - ensure all args are recognized
+ * @argc: number of args given to the tracer
+ * @argv: argument list
+ *
+ * Exits with 1 if there is/are unrecognized argument(s).
+ */
+void check_args_validity(int argc, char **argv)
+{
+    int i, j;
+
+    for(i = 1; i < argc; i++) {
+        /* it's the child's arguments from here on */
+        if(strcmp(argv[i], "--") == 0)
+            break;
+
+        int recognized = 0;
+        for(j = 0; j < help_list_count; j++) {
+            if(strcmp(argv[i], help_list[j].arg) == 0) {
+                recognized = 1;
+                i += help_list[j].num_vals;
+            }
+        }
+        if(!recognized) {
+            fprintf(stderr, "fssb: error: invalid option '%s'\n\n", argv[i]);
+            print_help();
+            exit(1);
+        }
+    }
+}
+
+/**
+ * help_requested - determine if the help text is requested by the user
+ * @argc: number of args given to the tracer
+ * @argv: argument list
+ *
+ * Returns 1 if help is requested, 0 otherwise.
+ */
+int help_requested(int argc, char **argv)
+{
+    int i, other_args = 0, show_help = 0;
+
+    for(i = 1; i < argc; i++) {
+        if(strcmp(argv[i], "-h") == 0)
+            show_help = 1;
+        else
+            other_args = 1;
+    }
+
+    if(!show_help)
+        return 0;
+
+    if(other_args)
+        fprintf(stderr, "`-h` must be the only argument if it is used.\n\n");
+
+    return 1;
+}
+
+/**
+ * print_help - print the help manual
+ */
+void print_help() {
+    fprintf(stdout, "Usage: fssb [OPTIONS] -- COMMAND\n");
+    fprintf(stdout, "\n\
+FSSB is a filesystem sandbox for Linux. It's useful if you want to run a\n\
+program but also protect your files and directories from modification.\n\n");
+
+    int i;
+    for(i = 0; i < help_list_count; i++) {
+        fprintf(stdout, "  %s", help_list[i].arg);
+        for(int j = 0; j < help_list[i].num_vals; j++)
+            fprintf(stdout, " ARG");
+        for(int j = 0; j < 15 - 4*help_list[i].num_vals; j++)
+            fprintf(stdout, " ");
+        fprintf(stdout, "%s\n", help_list[i].desc);
+    }
+
+    fprintf(stdout, "\n\
+You can find a more complete at https://github.com/adtac/fssb\n");
+}
+
+/**
+ * set_parameters - reads the command line arguments and sets the values
+ * @argc:     number of args given to the tracer
+ * @argv:     argument list
+ * @cleanup:  whether to cleanup all temp files at exit
+ * @log_file: file to log all output to
+ */
+void set_parameters(int argc,
+                    char **argv,
+                    int *cleanup,
+                    FILE **log_file,
+                    int *print_map)
+{
+    /* default values */
+    *cleanup = 0;
+    *log_file = stdout;
+    *print_map = 0;
+
+    int i;
+    for(i = 0; i < argc; i++) {
+        if(strcmp(argv[i], "-r") == 0)
+            *cleanup = 1;
+
+        if(strcmp(argv[i], "-m") == 0)
+            *print_map = 1;
+
+        if(strcmp(argv[i], "-o") == 0) {
+            struct stat sb;
+            if(i == argc - 1) {
+                fprintf(stderr, "fssb: error: no logging file specified\n");
+                exit(1);
+            }
+            *log_file = fopen(argv[i + 1], "w");
+            if(*log_file == NULL) {
+                fprintf(stderr, "fssb: error: cannot create log file %s\n",
+                                argv[i + 1]);
+                exit(1);
+            }
+            i++;
+        }
+    }
+}
+
+/**
+ * get_child_args_start_pos - get the position where the child args start
+ * @argc: number of args given to the tracer
+ * @argv: argument list
+ *
+ * Returns the point in the array where the child arguments begin.
+ */
+int get_child_args_start_pos(int argc, char **argv)
+{
+    int pos = 0;
+
+    while(pos < argc) {
+        if(strcmp(argv[pos], "--") == 0)
+            break;
+        pos++;
+    }
+
+    if(pos == argc) {
+        fprintf(stderr, "fssb: error: no `--` found in arguments\n");
+        fprintf(stderr, "usage: fssb -- <program> <args>\n");
+        exit(1);
+    }
+
+    if(pos == argc - 1) {
+        fprintf(stderr, "fssb: error: nothing found after `--`\n");
+        fprintf(stderr, "usage: fssb -- <program> <args>\n");
+        exit(1);
+    }
+
+    return pos + 1;
+}

arguments.h

@@ -0,0 +1,47 @@
+/**
+ * arguments.h - Argument handling.  Part of the FSSB project.
+ *
+ * Copyright (C) 2016 Adhityaa Chandrasekar
+ *
+ * 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 Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _ARGUMENT_H
+#define _ARGUMENT_H
+
+typedef struct {
+    char arg[3], desc[128];
+    int num_vals;
+} help;
+
+extern void build_help();
+
+extern void check_args_validity(int argc, char **argv);
+
+extern int help_requested(int argc, char **argv);
+
+extern void print_help();
+
+extern void set_parameters(int argc,
+                           char **argv,
+                           int *cleanup,
+                           FILE **log_file,
+                           int *print_map);
+
+extern int get_child_args_start_pos(int argc, char **argv);
+
+help *help_list;
+int help_list_count, help_list_allocated;
+
+#endif /* _ARGUMENT_H */