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

Grant Likely grant.likely at secretlab.ca
Thu Jul 7 04:43:46 EST 2011


On Tue, Jul 05, 2011 at 12:02:53PM -0700, Simon Glass wrote:
> This adds a new utility library for performing libfdt operations, and
> modifies dtget to use it.

Perhaps this patch should come before the dtget patch?

Otherwise looks okay.

> 
> Signed-off-by: Simon Glass <sjg at chromium.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
> 


More information about the devicetree-discuss mailing list