Fixed segmentation fault on invalid paths, cleaned up code

.gitignore

@@ -1,3 +1,5 @@
 bin/
 obj/
-TAGS
+GPATH
+GRTAGS
+GTAGS

src/cli.c

@@ -23,19 +23,46 @@
 #include <getopt.h>
 
 #include "cli.h"
-#include "crypto.h" /* New, maybe clean up the section on game crypto? */
+#include "crypto.h"
+
+
+/* Copies `optarg` into the out field of `p` and ensures that it ends in
+   a trailing path delimiter. */
+static void parse_output_path(const char *optarg, struct params *p) {
+    p->out_len = strlen(optarg);
+    p->out = malloc(p->out_len + 2);
+    strcpy(p->out, optarg);
+    if (p->out[p->out_len - 1] != '/') {
+        p->out[p->out_len] = '/';
+        p->out_len += 1;
+    }
+}
+
+
+/* Updates the game field of `p` to properly reflect the game ID
+   specified by the string, `optarg`. */
+static void parse_game_id(const char *optarg, struct params *p) {
+    if (!strcmp(optarg, "nekopara_volume_0"))
+        p->game = NEKOPARA_VOLUME_0;
+    else if (!strcmp(optarg, "nekopara_volume_0_steam"))
+        p->game = NEKOPARA_VOLUME_0_STEAM;
+    else if (!strcmp(optarg, "nekopara_volume_1"))
+        p->game = NEKOPARA_VOLUME_1;
+    else if (!strcmp(optarg, "nekopara_volume_1_steam"))
+        p->game = NEKOPARA_VOLUME_1_STEAM;
+}
 
 
 /* Returns a params structure parsed from `argv`. */
 struct params parse_args(int argc, char **argv) {
     struct params p = {0};
-    
+
     if (argc < 2) {
         p.mode = USAGE;
         return p;
     }
     p.mode = EXTRACT;
-    
+
     int cur = 0, opt_index = 0, count = 0;
     static struct option long_opts[] = {
         {"help", no_argument, NULL, 'h'},
@@ -63,24 +90,11 @@ struct params parse_args(int argc, char **argv) {
                 break;
             case 'o':
                 count++;
-                p.out_len = strlen(optarg);
-                p.out = malloc(p.out_len + 2);
-                strcpy(p.out, optarg);
-                if (p.out[p.out_len - 1] != '/') {
-                    p.out[p.out_len] = '/';
-                    p.out_len += 1;
-                }
+                parse_output_path(optarg, &p);
                 break;
             case 'g':
                 count++;
-                if (!strcmp(optarg, "nekopara_volume_0"))
-                    p.game = NEKOPARA_VOLUME_0;
-                else if (!strcmp(optarg, "nekopara_volume_0_steam"))
-                    p.game = NEKOPARA_VOLUME_0_STEAM;
-                else if (!strcmp(optarg, "nekopara_volume_1"))
-                    p.game = NEKOPARA_VOLUME_1;
-                else if (!strcmp(optarg, "nekopara_volume_1_steam"))
-                    p.game = NEKOPARA_VOLUME_1_STEAM;
+                parse_game_id(optarg, &p);
             case 'e':
                 p.mode = EXTRACT;
                 break;

src/cli.h

@@ -33,12 +33,12 @@ enum {
 
 /* Structure for storing options set from the command-line. */
 struct params {
-    int    mode; /* Current mode of operation. */
-    int    game; /* Which encryption keys to use. */
-    bool   verbose; /* Whether or not to output progress messages. */
+    int    mode;         /* Current mode of operation. */
+    int    game;         /* Which encryption keys to use. */
+    bool   verbose;      /* Whether or not to output progress messages. */
     int    vararg_index; /* Start index of paths in argv. */
-    char   *out; /* Path to extract files to. */
-    size_t out_len; /* Length of the output path string. */
+    char   *out;         /* Path to extract files to. */
+    size_t out_len;      /* Length of the output path string. */
 };
 
 /* Returns a params structure parsed from `argv`. */

src/crypto.h

@@ -33,8 +33,8 @@ enum {
 
 /* Structure containing game-specific encryption information. */
 struct game_key {
-    bool     uses_initial; /* Whether or not to use an initial key. */
-    uint32_t master; /* Master key specific to the game. */
+    bool     uses_initial;     /* Whether or not to use an initial key. */
+    uint32_t master;           /* Master key specific to the game. */
     uint8_t  fallback_initial; /* Fallback if initial key is 0. */
     uint8_t  fallback_primary; /* Fallback if primary key is 0. */
 };

src/header.h

@@ -27,11 +27,11 @@
 
 /* Structure representing the header section of an XP3 archive. */
 struct header {
-    char     magic[11]; /* Identifier for the archive. */
-    uint64_t info_offset; /* Offset to `table_size`. */
-    uint32_t version; /* Raw value containing the archive version. */
-    uint64_t table_size; /* The size of the table section. (?) */
-    uint8_t  flags; /* A flags variable for the archive. (?) */
+    char     magic[11];    /* Identifier for the archive. */
+    uint64_t info_offset;  /* Offset to `table_size`. */
+    uint32_t version;      /* Raw value containing the archive version. */
+    uint64_t table_size;   /* The size of the table section. (?) */
+    uint8_t  flags;        /* A flags variable for the archive. (?) */
     uint64_t table_offset; /* Offset to the archive table. */
 };
 

src/io.h

@@ -33,10 +33,10 @@ enum _location {
    position. The structure additionally maintains a `length` variable
    containing the stream's length. */
 struct stream {
-    size_t         len; /* Length of the stream. */
+    size_t         len;     /* Length of the stream. */
     char           *_start; /* Pointer to the stream's start. */
-    char           *_cur; /* Pointer to the current position. */
-    enum _location _loc; /* Location of the stream in memory. */
+    char           *_cur;   /* Pointer to the current position. */
+    enum _location _loc;    /* Location of the stream in memory. */
 };
 
 /* Allocates `len` bytes of non-zeroed memory and returns a new stream

src/main.c

@@ -1,4 +1,4 @@
-/* main.c -- Entry point to the program.
+/* main.c -- Command-line entry point to the Nekopack.
 
    Copyright (C) 2017 Jakob Kreuze, All Rights Reserved.
 
@@ -33,12 +33,7 @@
 #define EXIT_FAILURE 1
 #define EXIT_SUCCESS 0
 
-#define VERSION_STR "2.0.0a2"
-
-
-/* Pointer to a function to be mapped to entries in the table. */
-typedef void (*mapfn)(struct stream *archive, struct table_entry *e,
-                      struct params p);
+#define VERSION_STR "2.0.0"
 
 
 /* Writes usage information to stderr. */
@@ -65,7 +60,7 @@ static void print_help(void) {
            "   -l, --list\t\tList the contents of the archive.\n\n"
            "   -o, --output\t\tPath to extract files to.\n"
            "   -g, --game\t\tGame the archive is from. Required for file "
-           "decryption\n"
+           "decryption.\n"
            "   -q, --quiet\t\tDon't display information about extracted "
            "files.\n\n"
            "Supported games: nekopara_volume_0, nekopara_volume_0_steam,\n"
@@ -88,10 +83,9 @@ static struct stream *load_table(struct stream *s) {
 
 /* Creates any directories that do not already exist in `path`. */
 void make_dirs(char *path) {
-    struct stat tmp = {0};
-    char *buf = calloc(0x100, 1);
+    char *buf       = calloc(0x100, 1);
     char *buf_start = buf;
-
+    struct stat tmp = {0};
     for (int i = 0; i < 0x100 && path[i] != '\0'; i++) {
         if (path[i] == '/') {
             *buf++ = '/';
@@ -116,26 +110,20 @@ static char *get_path(struct params p, char *name) {
 }
 
 
-/* Basic mapfn for printing the filename of each entry. */
-static void list(struct stream *s, struct table_entry *e, struct params p) {
-    if (e->filename == NULL) {
-        fprintf(stderr, "Found File entry without matching eliF. Archive may "
-                "be corrupted.\n");
+/* Prints the filename of the entry specified by `e` to stdout. */
+static void list(struct table_entry *e) {
+    if (e->filename == NULL || e->segments == NULL) {
+        fprintf(stderr, "Inconsistency detected. Archive may be corrupted.\n");
         return;
     }
     printf("%s\n", e->filename);
 }
 
 
-/* Mapfn for extracting the contents of the archive. */
+/* Extracts the archive entry specified by `e` to disk. */
 static void extract(struct stream *s, struct table_entry *e, struct params p) {
-    if (e->filename == NULL) {
-        fprintf(stderr, "Found File entry without matching eliF. Archive may "
-                "be corrupted.\n");
-        return;
-    } else if (e->segments == NULL) {
-        fprintf(stderr, "Found eliF entry without matching File. Archive may "
-                "be corrupted.\n");
+    if (e->filename == NULL || e->segments == NULL) {
+        fprintf(stderr, "Inconsistency detected. Archive may be corrupted.\n");
         return;
     }
 
@@ -177,17 +165,30 @@ static void extract(struct stream *s, struct table_entry *e, struct params p) {
 }
 
 
-/* Maps `fn` to every table entry found in the archive at `path`. */
-static void map_entries(char *path, struct params p, mapfn fn) {
+/* Loads an XP3 archive and maps the function associated to the current
+   mode of operation to every entry. */
+static void map_entries(char *path, struct params p) {
     struct stream *archive = stream_from_file(path);
-    struct header *h       = read_header(archive);
+    if (archive == NULL) {
+        perror(path);
+        return;
+    }
+
+    struct header *h = read_header(archive);
     stream_seek(archive, h->table_offset, SEEK_SET);
 
     struct stream *table     = load_table(archive);
     struct table_entry *root = read_table(table);
 
-    for (struct table_entry *cur = root->next; cur != NULL; cur = cur->next)
-        fn(archive, cur, p);
+    for (struct table_entry *cur = root->next; cur != NULL; cur = cur->next) {
+        switch (p.mode) {
+            case LIST:
+                list(cur);
+                break;
+            case EXTRACT:
+                extract(archive, cur, p);
+        }
+    }
 
     entry_free(root);
     stream_free(table);
@@ -201,20 +202,18 @@ int main(int argc, char **argv) {
     switch (p.mode) {
         case USAGE:
             print_usage(argv[0]);
-            return 1;
+            params_free(p);
+            return EXIT_FAILURE;
         case VERSION:
             print_version();
             break;
         case HELP:
             print_help();
             break;
         case LIST:
-            for (int i = p.vararg_index; i < argc; i++)
-                map_entries(argv[i], p, list);
-            break;
         case EXTRACT:
             for (int i = p.vararg_index; i < argc; i++)
-                map_entries(argv[i], p, extract);
+                map_entries(argv[i], p);
     }
     params_free(p);
     return EXIT_SUCCESS;

src/table.h

@@ -27,20 +27,20 @@
 
 /* Structure representing one segment associated with a File entry. */
 struct segment {
-    bool     compressed; /* Whether or not the segment is compressed. */
-    uint64_t offset; /* Offset to the segment's beginning. */
-    uint64_t compressed_size; /* Size of compressed segment. */
+    bool     compressed;        /* Whether or not the segment is compressed. */
+    uint64_t offset;            /* Offset to the segment's beginning. */
+    uint64_t compressed_size;   /* Size of compressed segment. */
     uint64_t decompressed_size; /* Size of decompressed segment. */
 };
 
 /* Structure representing an entry in the archive's table section. */
 struct table_entry {
-    uint32_t           key; /* File-specific key for encryption. */
-    uint64_t           ctime; /* Timestamp of creation time. */
+    uint32_t           key;           /* File-specific key for encryption. */
+    uint64_t           ctime;         /* Timestamp of creation time. */
     uint64_t           segment_count; /* Number of segments. */
-    struct segment     **segments; /* Array of associated segments. */
-    char               *filename; /* String containing file's name. */
-    struct table_entry *next; /* Pointer to the next entry. */
+    char               *filename;     /* String containing file's name. */
+    struct segment     **segments;    /* Array of associated segments. */
+    struct table_entry *next;         /* Pointer to the next entry. */
 };