Add packed FS

examples/complete/pack.c

@@ -0,0 +1,71 @@
+// Copyright (c) Cesanta Software Limited
+// All rights reserved.
+
+// This program is used to pack arbitrary data into a C binary. It takes
+// a list of files as an input, and produces a .c data file that contains
+// contents of all these files as a collection of byte arrays.
+//
+// Usage:
+//   1. Compile this file:
+//      cc -o pack pack.c
+//
+//   2. Convert list of files into single .c:
+//      ./pack file1.data file2.data > fs.c
+//
+//   3. In your application code, you can access files using this function:
+//      const char *unpack(const char *file_name, size_t *size);
+//
+//   4. Build your app with fs.c:
+//      cc -o my_app my_app.c fs.c
+
+#include <stdio.h>
+#include <stdlib.h>
+
+static const char *code =
+    "const char *unpack(const char *name, size_t *size) {\n"
+    "  const struct packed_file *p;\n"
+    "  for (p = packed_files; p->name != NULL; p++) {\n"
+    "    if (strcmp(p->name, name) != 0) continue;\n"
+    "    if (size != NULL) *size = p->size - 1;\n"
+    "    return (const char *) p->data;\n"
+    "  }\n"
+    "  return NULL;\n"
+    "}\n";
+
+int main(int argc, char *argv[]) {
+  int i, j, ch;
+
+  printf("%s", "#include <stddef.h>\n");
+  printf("%s", "#include <string.h>\n");
+  printf("%s", "\n");
+
+  for (i = 1; i < argc; i++) {
+    FILE *fp = fopen(argv[i], "rb");
+    if (fp == NULL) exit(EXIT_FAILURE);
+
+    printf("static const unsigned char v%d[] = {", i);
+    for (j = 0; (ch = fgetc(fp)) != EOF; j++) {
+      if ((j % 12) == 0) printf("%s", "\n ");
+      printf(" %3u,", ch);
+    }
+    // Append zero byte at the end, to make text files appear in memory
+    // as nul-terminated strings.
+    printf("%s", " 0x00\n};\n");
+    fclose(fp);
+  }
+
+  printf("%s", "\nconst struct packed_file {\n");
+  printf("%s", "  const char *name;\n");
+  printf("%s", "  const unsigned char *data;\n");
+  printf("%s", "  size_t size;\n");
+  printf("%s", "} packed_files[] = {\n");
+
+  for (i = 1; i < argc; i++) {
+    printf("  {\"%s\", v%d, sizeof(v%d) },\n", argv[i], i, i);
+  }
+  printf("%s", "  {NULL, NULL, 0}\n");
+  printf("%s", "};\n\n");
+  printf("%s", code);
+
+  return EXIT_SUCCESS;
+}