git.ozlabs.org Git - ccan/blob - ccan/short_types/_info

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include "config.h"
   4
   5 /**
   6  * short_types - shorter names for standard integer types
   7  *
   8  * "C is a Spartan language, and so should your naming be."
   9  *      -- Linus Torvalds
  10  *
  11  * The short_types header provides for convenient abbreviations for the
  12  * posixly-damned uint32_t types.  If ccan/endian/endian.h is included,
  13  * it also provides be32/le32 for explicitly annotating types of specific
  14  * endian.
  15  *
  16  * Include this header, if only to stop people using these identifiers
  17  * for other things!
  18  *
  19  * Example:
  20  *      #include <stdint.h>
  21  *      #include <string.h>
  22  *      #include <stdio.h>
  23  *      #include <ccan/short_types/short_types.h>
  24  *
  25  *      // Print nonsensical numerical comparison of POSIX vs. short_types.
  26  *      #define stringify_1(x)  #x
  27  *      #define stringify(x)    stringify_1(x)
  28  *
  29  *      static void evaluate(size_t size, const char *posix, const char *sht,
  30  *                           unsigned int *posix_total, unsigned int *sht_total,
  31  *                           unsigned int *size_total)
  32  *      {
  33  *              printf("\t%ssigned %s: POSIX %zu%%, short %zu%%\n",
  34  *                     sht[0] == 'u' ? "un" : "",
  35  *                     sht+1,
  36  *                     strlen(posix)*100 / size,
  37  *                     strlen(sht)*100 / size);
  38  *              *posix_total += strlen(posix);
  39  *              *sht_total += strlen(sht);
  40  *              *size_total += size;
  41  *      }
  42  *
  43  *      #define EVALUATE(psx, short, pt, st, t)                         \
  44  *              evaluate(sizeof(psx), stringify(psx), stringify(sht), pt, st, t)
  45  *
  46  *      int main(void)
  47  *      {
  48  *              unsigned int posix_total = 0, sht_total = 0, size_total = 0;
  49  *
  50  *              printf("Comparing size of type vs size of name:\n");
  51  *
  52  *              EVALUATE(uint8_t, u8, &posix_total, &sht_total, &size_total);
  53  *              EVALUATE(int8_t, s8, &posix_total, &sht_total, &size_total);
  54  *              EVALUATE(uint16_t, u16, &posix_total, &sht_total, &size_total);
  55  *              EVALUATE(int16_t, s16, &posix_total, &sht_total, &size_total);
  56  *              EVALUATE(uint32_t, u32, &posix_total, &sht_total, &size_total);
  57  *              EVALUATE(int32_t, s32, &posix_total, &sht_total, &size_total);
  58  *              EVALUATE(uint64_t, u64, &posix_total, &sht_total, &size_total);
  59  *              EVALUATE(int64_t, s64, &posix_total, &sht_total, &size_total);
  60  *
  61  *              printf("Conclusion:\n"
  62  *                     "\tPOSIX is %u%% LESS efficient than binary.\n"
  63  *                     "\tshort_types.h is %u%% MORE efficient than binary.\n",
  64  *                     (posix_total - size_total) * 100 / size_total,
  65  *                     (size_total - sht_total) * 100 / size_total);
  66  *              return 0;
  67  *      }
  68  *
  69  * License: CC0 (Public domain)
  70  * Author: Rusty Russell <rusty@rustcorp.com.au>
  71  */
  72 int main(int argc, char *argv[])
  73 {
  74         if (argc != 2)
  75                 return 1;
  76
  77         if (strcmp(argv[1], "depends") == 0) {
  78                 return 0;
  79         }
  80
  81         if (strcmp(argv[1], "testdepends") == 0) {
  82                 printf("ccan/endian\n");
  83                 return 0;
  84         }
  85
  86         return 1;
  87 }