DTC: Add support for a C-like #include "file" mechanism.

Keeps track of open files in a stack, and assigns
a filenum to source positions for each lexical token.
Modified error reporting to show source file as well.
No policy on file directory basis has been decided.
Still handles stdin.

Tested on all arch/powerpc/boot/dts DTS files

Signed-off-by: Jon Loeliger <jdl@freescale.com>

1 files changed, 105 insertions, 0 deletions

diff --git a/srcpos.c b/srcpos.c
new file mode 100644
index 0000000..352b0fe
--- /dev/null
+++ b/srcpos.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright 2007 Jon Loeliger, Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+ *                                                                   USA
+ */
+
+#include "dtc.h"
+#include "srcpos.h"
+
+
+/*
+ * Record the complete unique set of opened file names.
+ * Primarily used to cache source position file names.
+ */
+#define MAX_N_FILE_NAMES	(100)
+
+const char *file_names[MAX_N_FILE_NAMES];
+static int n_file_names = 0;
+
+/*
+ * Like yylineno, this is the current open file pos.
+ */
+
+int srcpos_filenum = -1;
+
+
+
+FILE *dtc_open_file(const char *fname)
+{
+	FILE *f;
+
+	if (lookup_file_name(fname, 1) < 0)
+		die("Too many files opened\n");
+
+	if (streq(fname, "-"))
+		f = stdin;
+	else
+		f = fopen(fname, "r");
+
+	if (! f)
+		die("Couldn't open \"%s\": %s\n", fname, strerror(errno));
+
+	return f;
+}
+
+
+
+/*
+ * Locate and optionally add filename fname in the file_names[] array.
+ *
+ * If the filename is currently not in the array and the boolean
+ * add_it is non-zero, an attempt to add the filename will be made.
+ *
+ * Returns;
+ *    Index [0..MAX_N_FILE_NAMES) where the filename is kept
+ *    -1 if the name can not be recorded
+ */
+
+int lookup_file_name(const char *fname, int add_it)
+{
+	int i;
+
+	for (i = 0; i < n_file_names; i++) {
+		if (strcmp(file_names[i], fname) == 0)
+			return i;
+	}
+
+	if (add_it) {
+		if (n_file_names < MAX_N_FILE_NAMES) {
+			file_names[n_file_names] = strdup(fname);
+			return n_file_names++;
+		}
+	}
+
+	return -1;
+}
+
+
+const char *srcpos_filename_for_num(int filenum)
+{
+	if (0 <= filenum && filenum < n_file_names) {
+		return file_names[filenum];
+	}
+
+	return 0;
+}
+
+
+const char *srcpos_get_filename(void)
+{
+	return srcpos_filename_for_num(srcpos_filenum);
+}