summaryrefslogtreecommitdiffstats
path: root/dimension/tokenize.c
blob: 4eb6a6273346705d5d5ca5a1bfd360fce78d363f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
/*************************************************************************
 * Copyright (C) 2009 Tavian Barnes <tavianator@gmail.com>               *
 *                                                                       *
 * This file is part of Dimension.                                       *
 *                                                                       *
 * Dimension is free software; you can redistribute it and/or modify it  *
 * under the terms of the GNU General Public License as published by the *
 * Free Software Foundation; either version 3 of the License, or (at     *
 * your option) any later version.                                       *
 *                                                                       *
 * Dimension is distributed in the hope that it will be useful, but      *
 * WITHOUT ANY WARRANTY; without even the implied warranty of            *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU     *
 * General Public License for more details.                              *
 *                                                                       *
 * You should have received a copy of the GNU General Public License     *
 * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
 *************************************************************************/

#include "tokenize.h"
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <sys/mman.h>
#include <unistd.h>

static int
dmnsn_tokenize_comment(char *map, size_t size,
                       char **next, unsigned int *line, unsigned int *col)
{
  if (**next != '/')
    return 1;

  if (*(*next + 1) == '/') {
    /* A '//' comment block */
    do {
      ++*next;
    } while (*next - map < size && **next != '\n');

    ++*next;
    ++*line;
    *col = 0;
  } else if (*(*next + 1) == '*') {
    /* A '/*' comment block */
    do {
      ++col;
      if (**next == '\n') {
        ++line;
        col = 0;
      }

      ++*next;
    } while (*next - map < size - 1
             && !(**next == '*' && *(*next + 1) == '/'));
    *next += 2;
  } else {
    return 1;
  }

  return 0;
}

static int
dmnsn_tokenize_number(char *map, size_t size, dmnsn_token *token,
                      char **next, unsigned int *line, unsigned int *col)
{
  char *endf, *endi;

  strtoul(*next, &endi, 0);
  strtod(*next, &endf);
  if (endf > endi
      /* These *next conditions catch invalid octal integers being parsed as
         floats, eg 08 */
      && (*endi == '.' || *endi == 'e' || *endi == 'E' || *endi == 'p'
          || *endi == 'P'))
  {
    token->type = DMNSN_FLOAT;
    token->value = malloc(endf - *next + 1);
    strncpy(token->value, *next, endf - *next);
    token->value[endf - *next] = '\0';

    *col += endf - *next;
    *next = endf;
  } else if (endi > *next) {
    token->type = DMNSN_INT;
    token->value = malloc(endi - *next + 1);
    strncpy(token->value, *next, endi - *next);
    token->value[endi - *next] = '\0';

    *col += endi - *next;
    *next = endi;
  } else {
    return 1;
  }

  return 0;
}

dmnsn_array *
dmnsn_tokenize(FILE *file)
{
  if (fseeko(file, 0, SEEK_END) != 0) {
    fprintf(stderr, "Couldn't seek on input stream.\n");
    return NULL;
  }

  off_t size = ftello(file);

  int fd = fileno(file);
  if (fd == -1) {
    fprintf(stderr, "Couldn't get file descriptor to input stream.\n");
    return NULL;
  }

  char *map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0), *next = map;

  if (map == MAP_FAILED) {
    fprintf(stderr, "Couldn't mmap() input stream.\n");
    return NULL;
  }

  dmnsn_token token;
  dmnsn_array *tokens = dmnsn_new_array(sizeof(dmnsn_token));

  unsigned int line = 1, col = 0;
  unsigned int i;

  while (next - map < size) {
    /* Saves some code repetition */
    token.value = NULL;
    token.line  = line;
    token.col   = col;

    switch (*next) {
    case ' ':
    case '\r':
    case '\t':
    case '\f':
    case '\v':
      /* Skip whitespace */
      ++next;
      ++col;
      continue;

    case '\n':
      ++next;
      ++line;
      col = 0;
      continue;

    /* Macro to make basic symbol tokens easier */
    #define dmnsn_simple_token(c, tp)                                          \
    case c:                                                                    \
      token.type = tp;                                                         \
      break

    /* Some simple punctuation marks */
    dmnsn_simple_token('{', DMNSN_LBRACE);
    dmnsn_simple_token('}', DMNSN_RBRACE);
    dmnsn_simple_token('(', DMNSN_LPAREN);
    dmnsn_simple_token(')', DMNSN_RPAREN);
    dmnsn_simple_token('[', DMNSN_LBRACKET);
    dmnsn_simple_token(']', DMNSN_RBRACKET);
    dmnsn_simple_token('<', DMNSN_LT);
    dmnsn_simple_token('>', DMNSN_GT);
    dmnsn_simple_token('+', DMNSN_PLUS);
    dmnsn_simple_token('-', DMNSN_MINUS);
    dmnsn_simple_token('*', DMNSN_STAR);
    dmnsn_simple_token(',', DMNSN_COMMA);

    /* Possible comment */
    case '/':
      if (dmnsn_tokenize_comment(map, size, &next, &line, &col) == 0) {
        continue;
      } else {
        /* Just the normal punctuation mark */
        token.type = DMNSN_SLASH;
      }
      break;

    /* Numeric values */
    case '.': /* Number begins with a decimal point, as in `.2' */
    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9':
      if (dmnsn_tokenize_number(map, size, &token, &next, &line, &col) != 0) {
        fprintf(stderr, "Invalid numeric value on line %u, column %u.\n",
                line, col);
        goto bailout;
      }
      break;

    default:
      /* Unrecognised character */
      fprintf(stderr,
              "Unrecognized character 0x%X in input at line %u, column %u.\n",
              (unsigned int)*next, line, col);
      goto bailout;
    }

    dmnsn_array_push(tokens, &token);
    ++next;
    ++col;
  }

  munmap(map, size);
  return tokens;

 bailout:
  dmnsn_delete_tokens(tokens);
  munmap(map, size);
  return NULL;
}

void
dmnsn_delete_tokens(dmnsn_array *tokens)
{
  dmnsn_token *token;
  unsigned int i;
  for (i = 0; i < dmnsn_array_size(tokens); ++i) {
    token = dmnsn_array_at(tokens, i);
    free(token->value);
  }
  dmnsn_delete_array(tokens);
}

static const char *dmnsn_token_name(dmnsn_token_type token_type);

static void
dmnsn_print_token(FILE *file, dmnsn_token *token)
{
  if (token->value) {
    fprintf(file, "(%s \"%s\")", dmnsn_token_name(token->type), token->value);
  } else {
    fprintf(file, "%s", dmnsn_token_name(token->type));
  }
}

void
dmnsn_print_token_sexpr(FILE *file, dmnsn_array *tokens)
{
  unsigned int i;
  if (dmnsn_array_size(tokens) == 0) {
    fprintf(file, "()");
  } else {
    fprintf(file, "(");
    dmnsn_print_token(file, dmnsn_array_at(tokens, 0));

    for (i = 1; i < dmnsn_array_size(tokens); ++i) {
      fprintf(file, " ");
      dmnsn_print_token(file, dmnsn_array_at(tokens, i));
    }

    fprintf(file, ")");
  }

  fprintf(file, "\n");
}

static const char *
dmnsn_token_name(dmnsn_token_type token_type)
{
  switch (token_type) {
  /* Macro to shorten this huge switch */
  #define dmnsn_token_map(type, str)                                           \
  case type:                                                                   \
    return str;

  /* Punctuation */
  dmnsn_token_map(DMNSN_LBRACE,   "{");
  dmnsn_token_map(DMNSN_RBRACE,   "}")
  dmnsn_token_map(DMNSN_LPAREN,   "\\(");
  dmnsn_token_map(DMNSN_RPAREN,   "\\)");
  dmnsn_token_map(DMNSN_LBRACKET, "[");
  dmnsn_token_map(DMNSN_RBRACKET, "]");
  dmnsn_token_map(DMNSN_LT,       "<");
  dmnsn_token_map(DMNSN_GT,       ">");
  dmnsn_token_map(DMNSN_PLUS,     "+");
  dmnsn_token_map(DMNSN_MINUS,    "-");
  dmnsn_token_map(DMNSN_STAR,     "*");
  dmnsn_token_map(DMNSN_SLASH,    "/");
  dmnsn_token_map(DMNSN_COMMA,    ",");

  /* Numeric values */
  dmnsn_token_map(DMNSN_INT,   "int");
  dmnsn_token_map(DMNSN_FLOAT, "float");

  default:
    printf("Warning: unrecognised token %d.\n", (int)token_type);
    return "unrecognized-token";
  }
}