Simpler handling of Byte Order Mark (BOM)
diff --git a/lauxlib.c b/lauxlib.c
index 413d8f9..cba5df9 100644
--- a/lauxlib.c
+++ b/lauxlib.c
@@ -740,17 +740,18 @@
}
-static int skipBOM (LoadF *lf) {
- const char *p = "\xEF\xBB\xBF"; /* UTF-8 BOM mark */
- int c;
- lf->n = 0;
- do {
- c = getc(lf->f);
- if (c == EOF || c != *(const unsigned char *)p++) return c;
- lf->buff[lf->n++] = c; /* to be read by the parser */
- } while (*p != '\0');
- lf->n = 0; /* prefix matched; discard it */
- return getc(lf->f); /* return next character */
+/*
+** Skip an optional BOM at the start of a stream. If there is an
+** incomplete BOM (the first character is correct but the rest is
+** not), returns the first character anyway to force an error
+** (as no chunk can start with 0xEF).
+*/
+static int skipBOM (FILE *f) {
+ int c = getc(f); /* read first character */
+ if (c == 0xEF && getc(f) == 0xBB && getc(f) == 0xBF) /* correct BOM? */
+ return getc(f); /* ignore BOM and return next char */
+ else /* no (valid) BOM */
+ return c; /* return first character */
}
@@ -761,13 +762,13 @@
** first "valid" character of the file (after the optional BOM and
** a first-line comment).
*/
-static int skipcomment (LoadF *lf, int *cp) {
- int c = *cp = skipBOM(lf);
+static int skipcomment (FILE *f, int *cp) {
+ int c = *cp = skipBOM(f);
if (c == '#') { /* first line is a comment (Unix exec. file)? */
do { /* skip first line */
- c = getc(lf->f);
+ c = getc(f);
} while (c != EOF && c != '\n');
- *cp = getc(lf->f); /* skip end-of-line, if present */
+ *cp = getc(f); /* next character after comment, if present */
return 1; /* there was a comment */
}
else return 0; /* no comment */
@@ -789,12 +790,16 @@
lf.f = fopen(filename, "r");
if (lf.f == NULL) return errfile(L, "open", fnameindex);
}
- if (skipcomment(&lf, &c)) /* read initial portion */
- lf.buff[lf.n++] = '\n'; /* add line to correct line numbers */
- if (c == LUA_SIGNATURE[0] && filename) { /* binary file? */
- lf.f = freopen(filename, "rb", lf.f); /* reopen in binary mode */
- if (lf.f == NULL) return errfile(L, "reopen", fnameindex);
- skipcomment(&lf, &c); /* re-read initial portion */
+ lf.n = 0;
+ if (skipcomment(lf.f, &c)) /* read initial portion */
+ lf.buff[lf.n++] = '\n'; /* add newline to correct line numbers */
+ if (c == LUA_SIGNATURE[0]) { /* binary file? */
+ lf.n = 0; /* remove possible newline */
+ if (filename) { /* "real" file? */
+ lf.f = freopen(filename, "rb", lf.f); /* reopen in binary mode */
+ if (lf.f == NULL) return errfile(L, "reopen", fnameindex);
+ skipcomment(lf.f, &c); /* re-read initial portion */
+ }
}
if (c != EOF)
lf.buff[lf.n++] = c; /* 'c' is the first character of the stream */
diff --git a/testes/main.lua b/testes/main.lua
index 9def638..9187420 100644
--- a/testes/main.lua
+++ b/testes/main.lua
@@ -94,6 +94,33 @@
checkout("10\n2\n")
+-- testing BOM
+prepfile("\xEF\xBB\xBF")
+RUN('lua %s > %s', prog, out)
+checkout("")
+
+prepfile("\xEF\xBB\xBFprint(3)")
+RUN('lua %s > %s', prog, out)
+checkout("3\n")
+
+prepfile("\xEF\xBB\xBF# comment!!\nprint(3)")
+RUN('lua %s > %s', prog, out)
+checkout("3\n")
+
+-- bad BOMs
+prepfile("\xEF")
+NoRun("unexpected symbol", 'lua %s > %s', prog, out)
+
+prepfile("\xEF\xBB")
+NoRun("unexpected symbol", 'lua %s > %s', prog, out)
+
+prepfile("\xEFprint(3)")
+NoRun("unexpected symbol", 'lua %s > %s', prog, out)
+
+prepfile("\xEF\xBBprint(3)")
+NoRun("unexpected symbol", 'lua %s > %s', prog, out)
+
+
-- test option '-'
RUN('echo "print(arg[1])" | lua - -h > %s', out)
checkout("-h\n")
@@ -385,12 +412,10 @@
prepfile[[#comment in 1st line without \n at the end]]
RUN('lua %s', prog)
-prepfile[[#test line number when file starts with comment line
-debug = require"debug"
-print(debug.getinfo(1).currentline)
-]]
+-- first-line comment with binary file
+prepfile("#comment\n" .. string.dump(load("print(3)")))
RUN('lua %s > %s', prog, out)
-checkprogout('3\n')
+checkout('3\n')
-- close Lua with an open file
prepfile(string.format([[io.output(%q); io.write('alo')]], out))
