src/words.h

   1 #ifndef WORDS_H
   2 #define WORDS_H
   3
   4 #define _POSIX_C_SOURCE 200809L
   5 #include <stdbool.h>
   6 #include <stdint.h>
   7 #include <stdlib.h>
   8 #include <unistd.h>
   9 #include "try.h"
  10
  11 typedef struct {
  12         char* word;
  13         size_t len;
  14         bool eof;
  15 } ReadWord;
  16
  17 typedef struct {
  18         size_t size;
  19         size_t len;
  20         char** words;
  21 } Words;
  22
  23 static char** alloc(size_t const size) {
  24         return try_malloc(size * sizeof(char*));
  25 }
  26
  27 static bool adjust(size_t const len, size_t* const size) {
  28         if (len >= *size) {
  29                 out_of_memory_if(*size == SIZE_MAX);
  30                 if (*size > SIZE_MAX / 2u) {
  31                         *size = SIZE_MAX;
  32                 } else {
  33                         *size *= 2u;
  34                 }
  35                 return true;
  36         }
  37         return false;
  38 }
  39
  40 static Words new() {
  41         Words const words = {
  42                 .size = 2u * sizeof(*words.words),
  43                 .len = 0u,
  44                 .words = alloc(2u),
  45         };
  46         return words;
  47 }
  48
  49 static void push(Words words[static const 1], char* const s) {
  50         if (adjust(words->len * sizeof(*words->words), &words->size)) {
  51                 words->words = try_realloc(words->words, words->size);
  52         }
  53         words->words[words->len++] = s;
  54 }
  55
  56 static bool read_char(int const fd, char* const c) {
  57         ssize_t const len = read(fd, c, 1u);
  58         if (len == -1) {
  59                 pexit("read()");
  60         }
  61         return len;
  62 }
  63
  64 static ReadWord read_word(int const fd) {
  65         ReadWord w;
  66         w.len = 0u;
  67         char c;
  68         w.eof = !read_char(fd, &c);
  69         if (w.eof) {
  70                 w.word = NULL;
  71         } else {
  72                 size_t size = 2u;
  73                 w.word = try_malloc(size);
  74                 w.word[0] = c;
  75                 do {
  76                         if (!read_char(fd, &c)) {
  77                                 c = '\0';
  78                                 w.eof = true;
  79                         }
  80                         if (adjust(w.len, &size)) {
  81                                 w.word = try_realloc(w.word, size);
  82                         }
  83                         w.word[++w.len] = c;
  84                 } while (c);
  85         }
  86         return w;
  87 }
  88
  89 #endif