tools/cfsunpack: new tool

tools/cfspack/Makefile

@@ -1,4 +1,9 @@
-TARGETS = cfspack
+TARGETS = cfspack cfsunpack
+
+.PHONY: all
+all: $(TARGETS)
 
 cfspack: cfspack.c
+cfsunpack: cfsunpack.c
+$(TARGETS):
 	$(CC) -o $@ $^

tools/cfspack/cfsunpack.c

@@ -0,0 +1,93 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#define BLKSIZE 0x100
+#define HEADERSIZE 0x20
+#define MAX_FN_LEN 25   // 26 - null char
+
+bool ensuredir(char *path)
+{
+    char *s = path;
+    while (*s != '\0') {
+        if (*s == '/') {
+            *s = '\0';
+            struct stat path_stat;
+            if (stat(path, &path_stat) != 0) {
+                if (mkdir(path, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH) != 0) {
+                    return false;
+                }
+            }
+            *s = '/';
+        }
+        s++;
+    }
+    return true;
+}
+
+bool unpackblk(char *dstpath)
+{
+    char buf[MAX_FN_LEN+1];
+    if (fgets(buf, 3+1, stdin) == NULL) {
+        return false;
+    }
+    if (strcmp(buf, "CFS") != 0) {
+        return false;
+    }
+    int c = getchar();
+    uint8_t blkcnt = c;
+    if (blkcnt == 0) {
+        return false;
+    }
+    c = getchar();
+    uint16_t fsize = c & 0xff;
+    c = getchar();
+    fsize |= (c & 0xff) << 8;
+
+    if (fgets(buf, MAX_FN_LEN+1+1, stdin) == NULL) {
+        return false;
+    }
+    char fullpath[0x1000];
+    strcpy(fullpath, dstpath);
+    strcat(fullpath, "/");
+    strcat(fullpath, buf);
+    if (!ensuredir(fullpath)) {
+        return false;
+    }
+    int blksize = (BLKSIZE-HEADERSIZE)+(BLKSIZE*(blkcnt-1));
+    int skipcount = blksize - fsize;
+    FILE *fp = fopen(fullpath, "w");
+    while (fsize) {
+        c = getchar();
+        if (c == EOF) {
+            return false;
+        }
+        fputc(c, fp);
+        fsize--;
+    }
+    fclose(fp);
+    while (skipcount) {
+        getchar();
+        skipcount--;
+    }
+    return true;
+}
+
+int main(int argc, char *argv[])
+{
+    if (argc != 2) {
+        fprintf(stderr, "Usage: cfspack /path/to/dest\n");
+        return 1;
+    }
+    char *dstpath = argv[1];
+    // we fail if there isn't at least one block
+    if (!unpackblk(dstpath)) {
+        return 1;
+    }
+    while (unpackblk(dstpath));
+    return 0;
+}
+
+