tools/lib/subcmd/subcmd-util.h

   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 */