xref: /openbmc/linux/tools/lib/subcmd/subcmd-util.h (revision a06c488d)
1 #ifndef __SUBCMD_UTIL_H
2 #define __SUBCMD_UTIL_H
3 
4 #include <stdarg.h>
5 #include <stdlib.h>
6 #include <stdio.h>
7 
8 #define NORETURN __attribute__((__noreturn__))
9 
10 static inline void report(const char *prefix, const char *err, va_list params)
11 {
12 	char msg[1024];
13 	vsnprintf(msg, sizeof(msg), err, params);
14 	fprintf(stderr, " %s%s\n", prefix, msg);
15 }
16 
17 static NORETURN inline void die(const char *err, ...)
18 {
19 	va_list params;
20 
21 	va_start(params, err);
22 	report(" Fatal: ", err, params);
23 	exit(128);
24 	va_end(params);
25 }
26 
27 #define zfree(ptr) ({ free(*ptr); *ptr = NULL; })
28 
29 #define alloc_nr(x) (((x)+16)*3/2)
30 
31 /*
32  * Realloc the buffer pointed at by variable 'x' so that it can hold
33  * at least 'nr' entries; the number of entries currently allocated
34  * is 'alloc', using the standard growing factor alloc_nr() macro.
35  *
36  * DO NOT USE any expression with side-effect for 'x' or 'alloc'.
37  */
38 #define ALLOC_GROW(x, nr, alloc) \
39 	do { \
40 		if ((nr) > alloc) { \
41 			if (alloc_nr(alloc) < (nr)) \
42 				alloc = (nr); \
43 			else \
44 				alloc = alloc_nr(alloc); \
45 			x = xrealloc((x), alloc * sizeof(*(x))); \
46 		} \
47 	} while(0)
48 
49 static inline void *xrealloc(void *ptr, size_t size)
50 {
51 	void *ret = realloc(ptr, size);
52 	if (!ret && !size)
53 		ret = realloc(ptr, 1);
54 	if (!ret) {
55 		ret = realloc(ptr, size);
56 		if (!ret && !size)
57 			ret = realloc(ptr, 1);
58 		if (!ret)
59 			die("Out of memory, realloc failed");
60 	}
61 	return ret;
62 }
63 
64 #define astrcatf(out, fmt, ...)						\
65 ({									\
66 	char *tmp = *(out);						\
67 	if (asprintf((out), "%s" fmt, tmp ?: "", ## __VA_ARGS__) == -1)	\
68 		die("asprintf failed");					\
69 	free(tmp);							\
70 })
71 
72 static inline void astrcat(char **out, const char *add)
73 {
74 	char *tmp = *out;
75 
76 	if (asprintf(out, "%s%s", tmp ?: "", add) == -1)
77 		die("asprintf failed");
78 
79 	free(tmp);
80 }
81 
82 static inline int prefixcmp(const char *str, const char *prefix)
83 {
84 	for (; ; str++, prefix++)
85 		if (!*prefix)
86 			return 0;
87 		else if (*str != *prefix)
88 			return (unsigned char)*prefix - (unsigned char)*str;
89 }
90 
91 #endif /* __SUBCMD_UTIL_H */
92