tools/lib/subcmd/subcmd-util.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __SUBCMD_UTIL_H
   3 #define __SUBCMD_UTIL_H
   4
   5 #include <stdarg.h>
   6 #include <stdlib.h>
   7 #include <stdio.h>
   8 #include <linux/compiler.h>
   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         va_end(params);
  24         exit(128);
  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)
  53                 die("Out of memory, realloc failed");
  54         return ret;
  55 }
  56
  57 #define astrcatf(out, fmt, ...)                                         \
  58 ({                                                                      \
  59         char *tmp = *(out);                                             \
  60         if (asprintf((out), "%s" fmt, tmp ?: "", ## __VA_ARGS__) == -1) \
  61                 die("asprintf failed");                                 \
  62         free(tmp);                                                      \
  63 })
  64
  65 static inline void astrcat(char **out, const char *add)
  66 {
  67         char *tmp = *out;
  68
  69         if (asprintf(out, "%s%s", tmp ?: "", add) == -1)
  70                 die("asprintf failed");
  71
  72         free(tmp);
  73 }
  74
  75 #endif /* __SUBCMD_UTIL_H */