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