[PATCH 5/9] Add utilfdt for common functions, adjust dtget

[Simon Glass <sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>]

This adds a new utility library for performing libfdt operations, and
modifies dtget to use it.

Signed-off-by: Simon Glass <sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
---
 Makefile.dtget |    3 +-
 dtget.c        |   55 +++------------------------
 utilfdt.c      |  113 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 utilfdt.h      |   58 ++++++++++++++++++++++++++++
 4 files changed, 180 insertions(+), 49 deletions(-)
 create mode 100644 utilfdt.c
 create mode 100644 utilfdt.h

diff --git a/Makefile.dtget b/Makefile.dtget
index edda499..fd01055 100644
--- a/Makefile.dtget
+++ b/Makefile.dtget
@@ -6,7 +6,8 @@
 
 DTGET_SRCS = \
 	dtget.c \
-	util.c
+	util.c \
+	utilfdt.c
 
 DTGET_GEN_SRCS =
 
diff --git a/dtget.c b/dtget.c
index 0ee577c..cbcd4d2 100644
--- a/dtget.c
+++ b/dtget.c
@@ -15,8 +15,7 @@
 #include <libfdt.h>
 
 #include "util.h"
-
-#define FTDUMP_BUF_SIZE	65536
+#include "utilfdt.h"
 
 static void report_error(const char *where, int err)
 {
@@ -62,31 +61,16 @@ static void show_data(const char *format, int type, const char *data, int len)
 static int show_data_for_key(const void *blob, const char *format, int type,
 			     char *key)
 {
-	char *ptr, *prop;
+	char *prop;
 	int node, guess_node = 0;
 	const void *value;
 	int len;
 
-	/* First extract the property from the end */
-	ptr = strrchr(key, '/');
-	if (!ptr) {
-		fprintf(stderr, "No node found in key '%s'\n", key);
-		return 5;
-	}
-
-	if (ptr == key) {
-		guess_node = fdt_path_offset(blob, key);
-		node = fdt_path_offset(blob, "/");
-	} else {
-		*ptr = '\0';
-		node = fdt_path_offset(blob, key);
-		*ptr = '/';
-	}
+	node = util_decode_key(blob, key, &prop, &guess_node);
 	if (node < 0) {
 		report_error(key, node);
 		return 7;
 	}
-	prop = ptr + 1;
 	value = fdt_getprop(blob, node, prop, &len);
 	if (!value) {
 		report_error(prop, len);
@@ -103,40 +87,15 @@ static int show_data_for_key(const void *blob, const char *format, int type,
 static int do_dtget(const char *filename, const char *format, int type,
 		    char **key, int key_count)
 {
-	FILE *fp;
-	char *buf;
-	size_t size;
+	char *blob;
 	int i, ret;
 
-	if (strcmp(filename, "-") == 0) {
-		fp = stdin;
-	} else {
-		fp = fopen(filename, "rb");
-		if (fp == NULL) {
-			fprintf(stderr, "unable to open %s\n", filename);
-			return 10;
-		}
-	}
-
-	buf = malloc(FTDUMP_BUF_SIZE);
-	if (!buf) {
-		fprintf(stderr, "Couldn't allocate %d byte buffer\n",
-			FTDUMP_BUF_SIZE);
+	blob = util_read_fdt(filename);
+	if (!blob)
 		return 10;
-	}
 
-	size = fread(buf, 1, FTDUMP_BUF_SIZE, fp);
-	if (!feof(fp)) {
-		fprintf(stderr, "file too large (maximum is %d bytes)\n",
-			FTDUMP_BUF_SIZE);
-		return 10;
-	}
-	if (ferror(fp)) {
-		fprintf(stderr, "file read error\n");
-		return 10;
-	}
 	for (i = 0; i < key_count; i++) {
-		ret = show_data_for_key(buf, format, type, key[i]);
+		ret = show_data_for_key(blob, format, type, key[i]);
 		if (ret)
 			return ret;
 	}
diff --git a/utilfdt.c b/utilfdt.c
new file mode 100644
index 0000000..3cbd566
--- /dev/null
+++ b/utilfdt.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright 2001 The Chromium Authors, All Rights Reserved.
+ *
+ * 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 <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+
+#include "libfdt.h"
+#include "utilfdt.h"
+
+#define FTDUMP_BUF_SIZE	65536
+
+char *util_read_fdt(const char *filename)
+{
+	FILE *fp;
+	char *buf;
+	int size;
+
+	if (strcmp(filename, "-") == 0) {
+		fp = stdin;
+	} else {
+		fp = fopen(filename, "rb");
+		if (fp == NULL) {
+			fprintf(stderr, "unable to open '%s'\n", filename);
+			return NULL;
+		}
+	}
+
+	buf = malloc(FTDUMP_BUF_SIZE);
+	if (!buf) {
+		fprintf(stderr, "Couldn't allocate %d byte buffer\n",
+			FTDUMP_BUF_SIZE);
+		return NULL;
+	}
+
+	size = fread(buf, 1, FTDUMP_BUF_SIZE, fp);
+	if (!feof(fp)) {
+		fprintf(stderr, "file too large (maximum is %d bytes)\n",
+			FTDUMP_BUF_SIZE);
+	} else if (ferror(fp))
+		fprintf(stderr, "file read error\n");
+	else
+		return buf;
+	free(buf);
+	return NULL;
+}
+
+int util_write_fdt(const char *buf, const char *filename)
+{
+	FILE *fp;
+	size_t size, written;
+
+	if (strcmp(filename, "-") == 0) {
+		fp = stdout;
+	} else {
+		fp = fopen(filename, "wb");
+		if (fp == NULL) {
+			fprintf(stderr, "unable to open %s\n", filename);
+			return -1;
+		}
+	}
+
+	size = fdt_totalsize(buf);
+	written = fwrite(buf, 1, size, fp);
+	if (size != written) {
+		fprintf(stderr, "file write failed\n");
+		return -1;
+	}
+	return 0;
+}
+
+int util_decode_key(const char *blob, char *key, char **prop, int *guess_node)
+{
+	int node;
+	char *ptr;
+
+	/* First extract the property from the end */
+	*guess_node = 0;
+	ptr = strrchr(key, '/');
+	if (!ptr) {
+		fprintf(stderr, "No node found in key '%s'\n", key);
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	if (ptr == key) {
+		*guess_node = fdt_path_offset(blob, key);
+		node = fdt_path_offset(blob, "/");
+	} else {
+		*ptr = '\0';
+		node = fdt_path_offset(blob, key);
+		*ptr = '/';
+	}
+	*prop = ptr + 1;
+	return node;
+}
diff --git a/utilfdt.h b/utilfdt.h
new file mode 100644
index 0000000..79c218f
--- /dev/null
+++ b/utilfdt.h
@@ -0,0 +1,58 @@
+#ifndef _UTILFDT_H
+#define _UTILFDT_H
+
+/*
+ * Copyright 2001 The Chromium Authors, All Rights Reserved.
+ *
+ * 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
+ */
+
+/**
+ * Read a device tree file into a buffer.
+ *
+ * @param filename	The filename to read, or - for stdin
+ * @return		Poiner to allocated buffer containing fdt, or NULL
+ *			on error
+ */
+char *util_read_fdt(const char *filename);
+
+/**
+ * Write a device tree buffer to a file.
+ *
+ * @param filename	The filename to write, or - for stdout
+ * @param buf		Poiner to buffer containing fdt
+ * @return 0 if ok, -1 on error
+ */
+int util_write_fdt(const char *buf, const char *filename);
+
+/**
+ * Decode a node and property from a key string.
+ *
+ * This converts a key of the form /lcd/width into a node offset (/lcd) and
+ * a property (width).
+ *
+ * @param blob		Device tree blob
+ * @param key		Key string to decode
+ * @param prop		Returns pointer to property string within key
+ * @param guess_node	Normally <= 0, but if not then this is the offset of
+ *			a node that the caller MAY be referring to. For example
+ *			if key="/width" and there is a node /width, then
+ *			guess_node will return the offset of /width. It is used
+ *			to print a helpful error message.
+ */
+int util_decode_key(const char *blob, char *key, char **prop, int *guess_node);
+
+#endif /* _UTILFDT_H */
-- 
1.7.3.1