--embed-file option in emcc

emcc

@@ -181,6 +181,11 @@ Options that are modified or new in %s include:
                               will be run). Note that this by itself
                               will not minify the code (closure does
                               that)
+  --embed-file <filename>  A file to embed inside the generated
+                           JavaScript. The compiled code will be able
+                           to access the file in the current directory
+                           with the same basename as given here (that is,
+                           just the filename, without a path to it).
   --shell-file <path>      The path name to a skeleton HTML file used
                            when generating HTML output. The shell file
                            used needs to have this token inside it:
@@ -311,6 +316,7 @@ try:
   closure = None
   js_transform = None
   compress_whitespace = None
+  embed_files = []
   shell_path = shared.path_from_root('src', 'shell.html')
 
   def check_bad_eq(arg):
@@ -344,6 +350,11 @@ try:
       compress_whitespace = int(newargs[i+1])
       newargs[i] = ''
       newargs[i+1] = ''
+    elif newargs[i].startswith('--embed-file'):
+      check_bad_eq(newargs[i])
+      embed_files.append(newargs[i+1])
+      newargs[i] = ''
+      newargs[i+1] = ''
     elif newargs[i] == '-MF': # clang cannot handle this, so we fake it
       f = open(newargs[i+1], 'w')
       f.write('\n')
@@ -662,6 +673,17 @@ try:
   final = shared.Building.emscripten(final, append_ext=False)
   if DEBUG: save_intermediate('original')
 
+  # Embed files
+  if len(embed_files) > 0:
+    if DEBUG: print >> sys.stderr, 'emcc: embedding files'
+    src = open(final).read().replace(
+      '// {{PRE_RUN_ADDITIONS}}',
+      '\n'.join(map(lambda embed_file: "FS.createDataFile('/', '%s', %s, true, false);" % (os.path.basename(embed_file), str(map(ord, open(embed_file, 'rb').read()))), embed_files))
+    )
+    final += '.ef.js'
+    open(final, 'w').write(src)
+    if DEBUG: save_intermediate('embedded_files')
+
   # Apply a source code transformation, if requested
   if js_transform:
     shutil.copyfile(final, final + '.tr.js')

tests/runner.py

@@ -6150,6 +6150,24 @@ f.close()
       Popen([EMCC, os.path.join(self.get_dir(), 'main.cpp'), '-L' + os.path.join(self.get_dir(), 'libdir'), '-lfile'], stdout=PIPE, stderr=STDOUT).communicate()
       self.assertContained('hello from lib', run_js(os.path.join(self.get_dir(), 'a.out.js')))
 
+    def test_emcc_embed_file(self):
+      open(os.path.join(self.get_dir(), 'somefile.txt'), 'w').write('''hello from a file with lots of data and stuff in it thank you very much''')
+      open(os.path.join(self.get_dir(), 'main.cpp'), 'w').write(r'''
+        #include <stdio.h>
+        int main() {
+          FILE *f = fopen("somefile.txt", "r");
+          char buf[100];
+          fread(buf, 1, 20, f);
+          buf[20] = 0;
+          fclose(f);
+          printf("|%s|\n", buf);
+          return 0;
+        }
+      ''')
+
+      Popen([EMCC, os.path.join(self.get_dir(), 'main.cpp'), '--embed-file', 'somefile.txt']).communicate()
+      self.assertContained('|hello from a file wi|', run_js(os.path.join(self.get_dir(), 'a.out.js')))
+
     def test_eliminator(self):
       input = open(path_from_root('tools', 'eliminator', 'eliminator-test.js')).read()
       expected = open(path_from_root('tools', 'eliminator', 'eliminator-test-output.js')).read()