1 #ifndef UTIL_H
2 #define UTIL_H
3 
4 #include <stdarg.h>
5 #include <stdbool.h>
6 #include <getopt.h>
7 
8 /*
9  * Copyright 2011 The Chromium Authors, All Rights Reserved.
10  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License as
14  * published by the Free Software Foundation; either version 2 of the
15  * License, or (at your option) any later version.
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20  *  General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this program; if not, write to the Free Software
24  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
25  *                                                                   USA
26  */
27 
28 #ifdef __GNUC__
29 #define PRINTF(i, j)	__attribute__((format (printf, i, j)))
30 #define NORETURN	__attribute__((noreturn))
31 #else
32 #define PRINTF(i, j)
33 #define NORETURN
34 #endif
35 
36 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
37 
38 #define stringify(s)	stringify_(s)
39 #define stringify_(s)	#s
40 
die(const char * str,...)41 static inline void NORETURN PRINTF(1, 2) die(const char *str, ...)
42 {
43 	va_list ap;
44 
45 	va_start(ap, str);
46 	fprintf(stderr, "FATAL ERROR: ");
47 	vfprintf(stderr, str, ap);
48 	va_end(ap);
49 	exit(1);
50 }
51 
xmalloc(size_t len)52 static inline void *xmalloc(size_t len)
53 {
54 	void *new = malloc(len);
55 
56 	if (!new)
57 		die("malloc() failed\n");
58 
59 	return new;
60 }
61 
xrealloc(void * p,size_t len)62 static inline void *xrealloc(void *p, size_t len)
63 {
64 	void *new = realloc(p, len);
65 
66 	if (!new)
67 		die("realloc() failed (len=%zd)\n", len);
68 
69 	return new;
70 }
71 
72 extern char *xstrdup(const char *s);
73 extern char *xstrndup(const char *s, size_t len);
74 
75 extern int PRINTF(2, 3) xasprintf(char **strp, const char *fmt, ...);
76 extern char *join_path(const char *path, const char *name);
77 
78 /**
79  * Check a property of a given length to see if it is all printable and
80  * has a valid terminator. The property can contain either a single string,
81  * or multiple strings each of non-zero length.
82  *
83  * @param data	The string to check
84  * @param len	The string length including terminator
85  * Return: 1 if a valid printable string, 0 if not
86  */
87 bool util_is_printable_string(const void *data, int len);
88 
89 /*
90  * Parse an escaped character starting at index i in string s.  The resulting
91  * character will be returned and the index i will be updated to point at the
92  * character directly after the end of the encoding, this may be the '\0'
93  * terminator of the string.
94  */
95 char get_escape_char(const char *s, int *i);
96 
97 /**
98  * Read a device tree file into a buffer. This will report any errors on
99  * stderr.
100  *
101  * @param filename	The filename to read, or - for stdin
102  * Return: Pointer to allocated buffer containing fdt, or NULL on error
103  */
104 char *utilfdt_read(const char *filename);
105 
106 /**
107  * Like utilfdt_read(), but also passes back the size of the file read.
108  *
109  * @param len		If non-NULL, the amount of data we managed to read
110  */
111 char *utilfdt_read_len(const char *filename, off_t *len);
112 
113 /**
114  * Read a device tree file into a buffer. Does not report errors, but only
115  * returns them. The value returned can be passed to strerror() to obtain
116  * an error message for the user.
117  *
118  * @param filename	The filename to read, or - for stdin
119  * @param buffp		Returns pointer to buffer containing fdt
120  * Return: 0 if ok, else an errno value representing the error
121  */
122 int utilfdt_read_err(const char *filename, char **buffp);
123 
124 /**
125  * Like utilfdt_read_err(), but also passes back the size of the file read.
126  *
127  * @param len		If non-NULL, the amount of data we managed to read
128  */
129 int utilfdt_read_err_len(const char *filename, char **buffp, off_t *len);
130 
131 /**
132  * Write a device tree buffer to a file. This will report any errors on
133  * stderr.
134  *
135  * @param filename	The filename to write, or - for stdout
136  * @param blob		Poiner to buffer containing fdt
137  * Return: 0 if ok, -1 on error
138  */
139 int utilfdt_write(const char *filename, const void *blob);
140 
141 /**
142  * Write a device tree buffer to a file. Does not report errors, but only
143  * returns them. The value returned can be passed to strerror() to obtain
144  * an error message for the user.
145  *
146  * @param filename	The filename to write, or - for stdout
147  * @param blob		Poiner to buffer containing fdt
148  * Return: 0 if ok, else an errno value representing the error
149  */
150 int utilfdt_write_err(const char *filename, const void *blob);
151 
152 /**
153  * Decode a data type string. The purpose of this string
154  *
155  * The string consists of an optional character followed by the type:
156  *	Modifier characters:
157  *		hh or b	1 byte
158  *		h	2 byte
159  *		l	4 byte, default
160  *
161  *	Type character:
162  *		s	string
163  *		i	signed integer
164  *		u	unsigned integer
165  *		x	hex
166  *
167  * TODO: Implement ll modifier (8 bytes)
168  * TODO: Implement o type (octal)
169  *
170  * @param fmt		Format string to process
171  * @param type		Returns type found(s/d/u/x), or 0 if none
172  * @param size		Returns size found(1,2,4,8) or 4 if none
173  * Return: 0 if ok, -1 on error (no type given, or other invalid format)
174  */
175 int utilfdt_decode_type(const char *fmt, int *type, int *size);
176 
177 /*
178  * This is a usage message fragment for the -t option. It is the format
179  * supported by utilfdt_decode_type.
180  */
181 
182 #define USAGE_TYPE_MSG \
183 	"<type>\ts=string, i=int, u=unsigned, x=hex\n" \
184 	"\tOptional modifier prefix:\n" \
185 	"\t\thh or b=byte, h=2 byte, l=4 byte (default)";
186 
187 /**
188  * Print property data in a readable format to stdout
189  *
190  * Properties that look like strings will be printed as strings. Otherwise
191  * the data will be displayed either as cells (if len is a multiple of 4
192  * bytes) or bytes.
193  *
194  * If len is 0 then this function does nothing.
195  *
196  * @param data	Pointers to property data
197  * @param len	Length of property data
198  */
199 void utilfdt_print_data(const char *data, int len);
200 
201 /**
202  * Show source version and exit
203  */
204 void NORETURN util_version(void);
205 
206 /**
207  * Show usage and exit
208  *
209  * This helps standardize the output of various utils.  You most likely want
210  * to use the usage() helper below rather than call this.
211  *
212  * @param errmsg	If non-NULL, an error message to display
213  * @param synopsis	The initial example usage text (and possible examples)
214  * @param short_opts	The string of short options
215  * @param long_opts	The structure of long options
216  * @param opts_help	An array of help strings (should align with long_opts)
217  */
218 void NORETURN util_usage(const char *errmsg, const char *synopsis,
219 			 const char *short_opts,
220 			 struct option const long_opts[],
221 			 const char * const opts_help[]);
222 
223 /**
224  * Show usage and exit
225  *
226  * If you name all your usage variables with usage_xxx, then you can call this
227  * help macro rather than expanding all arguments yourself.
228  *
229  * @param errmsg	If non-NULL, an error message to display
230  */
231 #define usage(errmsg) \
232 	util_usage(errmsg, usage_synopsis, usage_short_opts, \
233 		   usage_long_opts, usage_opts_help)
234 
235 /**
236  * Call getopt_long() with standard options
237  *
238  * Since all util code runs getopt in the same way, provide a helper.
239  */
240 #define util_getopt_long() getopt_long(argc, argv, usage_short_opts, \
241 				       usage_long_opts, NULL)
242 
243 /* Helper for aligning long_opts array */
244 #define a_argument required_argument
245 
246 /* Helper for usage_short_opts string constant */
247 #define USAGE_COMMON_SHORT_OPTS "hV"
248 
249 /* Helper for usage_long_opts option array */
250 #define USAGE_COMMON_LONG_OPTS \
251 	{"help",      no_argument, NULL, 'h'}, \
252 	{"version",   no_argument, NULL, 'V'}, \
253 	{NULL,        no_argument, NULL, 0x0}
254 
255 /* Helper for usage_opts_help array */
256 #define USAGE_COMMON_OPTS_HELP \
257 	"Print this help and exit", \
258 	"Print version and exit", \
259 	NULL
260 
261 /* Helper for getopt case statements */
262 #define case_USAGE_COMMON_FLAGS \
263 	case 'h': usage(NULL); \
264 	case 'V': util_version(); \
265 	case '?': usage("unknown option");
266 
267 #endif /* UTIL_H */
268