Merge branch 'incoming' of github.com:hyperlogic/emscripten into incoming

2 files changed, 29 insertions, 4 deletions

diff --git a/src/library.js b/src/library.js
index 2efb7a6f..e79caa4c 100644
--- a/src/library.js
+++ b/src/library.js
@@ -3576,14 +3576,14 @@ LibraryManager.library = {
     return -1;
   },
   fscanf__deps: ['$FS', '__setErrNo', '$ERRNO_CODES',
-                 '_scanString', 'getc', 'ungetc'],
+                 '_scanString', 'fgetc', 'fseek', 'ftell'],
   fscanf: function(stream, format, varargs) {
     // int fscanf(FILE *restrict stream, const char *restrict format, ... );
     // http://pubs.opengroup.org/onlinepubs/000095399/functions/scanf.html
     if (FS.streams[stream]) {
-      var stack = [];
-      var get = function() { var ret = _fgetc(stream); stack.push(ret); return ret };
-      var unget = function(c) { return _ungetc(stack.pop(), stream) };
+      var i = _ftell(stream), SEEK_SET = 0;
+      var get = function () { i++; return _fgetc(stream); };
+      var unget = function () { _fseek(stream, --i, SEEK_SET); };
       return __scanString(format, get, unget, varargs);
     } else {
       return -1;
diff --git a/tests/runner.py b/tests/runner.py
index afb71ad9..37fb2bbb 100755
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -6363,6 +6363,31 @@ def process(filename):
       self.emcc_args += ['--embed-file', 'eol.txt']
       self.do_run(src, 'SUCCESS\n')
 
+    def test_fscanf(self):
+      if self.emcc_args is None: return self.skip('requires emcc')
+      open(os.path.join(self.get_dir(), 'three_numbers.txt'), 'w').write('''-1 0.1 -.1''')
+      src = r'''
+        #include <stdio.h>
+        #include <assert.h>
+        #include <float.h>
+        int main()
+        {
+            float x = FLT_MAX, y = FLT_MAX, z = FLT_MAX;
+
+            FILE* fp = fopen("three_numbers.txt", "r");
+            if (fp) {
+                int match = fscanf(fp, " %f %f %f ", &x, &y, &z);
+                printf("match = %d\n", match);
+                printf("x = %0.1f, y = %0.1f, z = %0.1f\n", x, y, z);
+            } else {
+                printf("failed to open three_numbers.txt\n");
+            }
+            return 0;
+        }
+      '''
+      self.emcc_args += ['--embed-file', 'three_numbers.txt']
+      self.do_run(src, 'match = 3\nx = -1.0, y = 0.1, z = -0.1\n')
+
     def test_folders(self):
       add_pre_run = '''
 def process(filename):