aboutsummaryrefslogtreecommitdiff
path: root/toys/pending/find.c
blob: 615f0c13bbc49ebe8c0d987eb8ed1fb114b7a152 (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
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
/* vi: set sw=4 ts=4:
 *
 * find.c - find files matching a criteria
 *
 * Copyright 2012 Tim Bird <tbird20d@gmail.com>
 *
 * See http://opengroup.org/onlinepubs/9699919799/utilities/find.html

USE_FIND(NEWTOY(find, "?", TOYFLAG_USR|TOYFLAG_BIN))

config FIND
  bool "find"
  default n
  help
    usage: find [<dir>] [<options]

    -name <pattern>    match pattern
    -type [fcdl]       match file type
    !, -a, -o          not, and , or
    (, )               group expressions  
    -mtime [-+]n       match file modification time (to within 24 hours)
    \t\t               +=greater (older) than, -=less (younger) than
*/

/* To Do:
 * -exec action
 */ 

#define FOR_find
#include "toys.h"

GLOBALS(
  char *dir;
)

#define SECONDS_PER_DAY (24*60*60)

int have_action;

struct filter_node {
  struct filter_node *next;
  int op;
  union {
    char *name_regex;
    struct {
      char time_op;
      time_t time;
    } t;
    mode_t type;
    struct {
      int arg_path_index;
      char **exec_args;
    } e;
  } data;
};

static struct filter_node *filter_root;

/* filter operation types */
#define OP_UNKNOWN	0
#define OP_OR		2
#define OP_AND		3
#define OP_NOT		4

#define LPAREN		1 
#define RPAREN		5 

#define MAX_OP		5

#define CHECK_NAME	7
#define CHECK_MTIME	8
#define CHECK_TYPE	9

#define ACTION_PRINT	20
#define ACTION_PRINT0	21
#define ACTION_EXEC	22

#define TEST_LT		0
#define TEST_EQ		1
#define TEST_GT		2

/* executes the command for a filter node
 * return the program return value (0=success)
 */
static int do_exec(struct filter_node *filter, struct dirtree *node)
{
  char *path = NULL;
  int plen;
  char **arg_array;
  pid_t pid;
  int status;

  arg_array = filter->data.e.exec_args;
  if (filter->data.e.arg_path_index) {
    path = dirtree_path(node, &plen);
    arg_array[filter->data.e.arg_path_index] = path;
  }

  if (!(pid = fork())) xexec(arg_array);
  free(path);
  waitpid(pid, &status, 0);

  return WEXITSTATUS(status);
}

/* prefix evaluator */
/* returns 0 for failure or 1 for success */
static int evaluate(struct filter_node *filter, struct dirtree *node,
  struct filter_node **fnext)
{
  int result;
  char *path;
  int plen = 0;
  struct stat st_buf;
  time_t node_time;
  int op;
  static int skip = 0;

  /* if no filters, success */
  if (!filter) {
    *fnext = NULL;
    return 1;
  }
  op = filter->op;

  if (op==OP_NOT) return !evaluate(filter->next, node, fnext);

  if (op==OP_OR || op==OP_AND) {
    result = evaluate(filter->next, node, fnext);
    if(!skip) {
      if (op==OP_OR) {
        skip = result;
        result = evaluate(*fnext, node, fnext) || result;
      } else {
        skip = !result;
        result = evaluate(*fnext, node, fnext) && result;
      }
      skip = 0;
    }
    else result = evaluate(*fnext, node, fnext);
    return result;
  }

  // we're down to single operations, mark our position
  *fnext = filter->next;
  if(skip) return 0;

  // TODO: Do a regex comparison
  if (op==CHECK_NAME)
    return !strcmp(filter->data.name_regex, node->name);

  if (op==CHECK_MTIME) {
    // do mtime check
    path = dirtree_path(node, &plen);
    result = stat(path,  &st_buf);
    free(path);
    if (result<0) return 0;

    node_time = st_buf.st_mtime/SECONDS_PER_DAY;
    result = 1;
    switch (filter->data.t.time_op) {
      /* do time compare here */
      case TEST_LT:
        /* FIXTHIS - should result be < or <= ?*/
        if (node_time > filter->data.t.time) result = 0;
        break;
      case TEST_GT:
        if (node_time < filter->data.t.time) result = 0;
        break;
      case TEST_EQ:
        if (node_time != filter->data.t.time) result = 0;
        break;
      default:
        /* how'd I get here? */
        result = 0;
        break;
    }
    return result;

  }
  if (op==CHECK_TYPE) {
    path = dirtree_path(node, &plen);
    result = lstat(path,  &st_buf);
    free(path);
    if (result<0) return 0;
    return (st_buf.st_mode & S_IFMT) == filter->data.type;
  }


  if (op==ACTION_PRINT || op==ACTION_PRINT0) {
    char terminator = (op==ACTION_PRINT)*'\n';

    path = dirtree_path(node, &plen);
    printf("%s%c", path, terminator);
    free(path);
    return 1;
  }

  if (op==ACTION_EXEC) return !do_exec(filter, node);

  error_msg("Ran out of operations in filter list!");
  return 1;
}

static int check_node_callback(struct dirtree *node)
{
  char *path;
  int plen = 0;
  int result;
  struct filter_node *junk;

  /* only recurse on "." at the root */
  /* so, don't recurse on 1) non-root "." and 2) any ".." */

  if (node->name[0] == '.' && 
    ((!node->name[1] && node->parent) ||
    (node->name[1]=='.' && !node->name[2])))
    return 0;

  result = evaluate(filter_root, node, &junk);
  if (result & !have_action) {
    /* default action is just print the path */
    path = dirtree_path(node, &plen);
    printf("%s\n", path);
    free(path);
  }
  return DIRTREE_RECURSE;
}


static void build_filter_list(void)
{
  struct filter_node *node_list, *op_stack, *node, *op_node, *next;
  char *arg, **arg_array;
  int i, j;
  int prevop = 0;

  /* part optargs here and build a filter list in prefix format */

  TT.dir = ".";
  node_list = NULL;
  have_action = 0;
  for(i=0; toys.optargs[i]; i++) {
    node = (struct filter_node *)
      xmalloc(sizeof(struct filter_node));
    node->op = OP_UNKNOWN;
    arg = toys.optargs[i];
    if (!strcmp(arg, "-o")) node->op = OP_OR;
    if (!strcmp(arg, "-a")) node->op = OP_AND;
    if (!strcmp(arg, "!")) node->op = OP_NOT;
    if (!strcmp(arg, "(")) node->op = LPAREN;
    if (!strcmp(arg, ")")) node->op = RPAREN;

    if (!strcmp(arg, "-name")) {
      node->op = CHECK_NAME;
      arg = toys.optargs[++i];
      if (!arg) error_exit("Missing argument to -name");
      node->data.name_regex = arg;
    }

    if (!strcmp(arg, "-mtime")) {
      node->op = CHECK_MTIME;
      arg = toys.optargs[++i];
      if (!arg) error_exit("Missing argument to -mtime");
      switch(arg[0]) {
        case '+':
          node->data.t.time_op=TEST_GT;
          arg++;
          break;
        case '-':
          node->data.t.time_op=TEST_LT;
          arg++;
          break;
        default:
          node->data.t.time_op=TEST_EQ;
          break;
      }
      /* convert to days (very crudely) */
      node->data.t.time = atoi(arg)/SECONDS_PER_DAY;
    }

    if (!strcmp(arg, "-type")) {
      mode_t types[]={S_IFREG,S_IFDIR,S_IFCHR,S_IFBLK,S_IFLNK,S_IFSOCK,S_IFIFO};
      int j;

      node->op = CHECK_TYPE;
      arg = toys.optargs[++i];
      if (!arg) error_exit("Missing argument to -type");
      if (-1 == (j = stridx("fdcblsp", *arg)))
        error_exit("bad type '%s'", arg);
      else node->data.type = types[j];
    }
    if (!strcmp(arg, "-print")) {
      node->op = ACTION_PRINT;
      have_action = 1;
    }
    if (!strcmp(arg, "-print0")) {
      node->op = ACTION_PRINT0;
      have_action = 1;
    }
    if (!strcmp(arg, "-exec")) {
      node->op = ACTION_EXEC;
      have_action = 1;
      arg_array = xmalloc(sizeof(char *));
      arg = toys.optargs[++i];
      for (j = 0; arg && strcmp(arg, ";"); j++) {
        /* new method */
        arg_array = xrealloc(arg_array, sizeof(char *) * (j+2));
        arg_array[j] = arg;
        if (!strcmp(arg, "{}")) node->data.e.arg_path_index = j;

        arg = toys.optargs[++i];
      }
      if (!arg) error_exit("need ';' in exec");
      arg_array[j] = 0;
      node->data.e.exec_args = arg_array;
    }
    if (node->op == OP_UNKNOWN) {
      if (arg[0] == '-') error_exit("bad option '%s'", arg);
      else TT.dir = arg;
    }  else {
      // add OP_AND where necessary
      if (node_list) {
        int o1 = node_list->op, o2 = node->op;
        if ((o1>MAX_OP && o2>MAX_OP) ||
           (o1==RPAREN && o2>=OP_NOT && o2!=RPAREN) ||
           (o1>=OP_NOT && o1!=LPAREN && o2==LPAREN)) {
          struct filter_node *n = (struct filter_node *)
                                  xmalloc(sizeof(struct filter_node));
          n->op = OP_AND;
          n->next = node_list;
          node_list = n;
        }
      }
      /* push node */
      node->next = node_list;;
      node_list = node;
    }

  }

  /* now convert from infix to prefix */
  filter_root = NULL;
  op_stack = NULL;
  node = node_list;
  while( node ) {
    int op = node->op;
    next = node->next;
    if (op==LPAREN || op==RPAREN) {
      free(node);
      node = 0;
    }
    if (op<=MAX_OP) {
      if (prevop > op) {
        /* pop opstack to output */
        op_node = op_stack;
        while (op_node) {
          /* remove from op_stack */
          op_stack = op_node->next;
          /* push to output */
          op_node->next = filter_root;
          filter_root = op_node;
          /* get next node */
          op_node = op_stack;
        }
      }
      if (node) {
        /* push to opstack */
        node->next = op_stack;
        op_stack = node;
      }
      prevop = op*(op!=RPAREN);
    }
    else {
        /* push to output */
        node->next = filter_root;
        filter_root = node;
    }
    node = next;
  }
  /* end of input - push opstack to output */
  /* pop opstack to output till empty */
  op_node = op_stack;
  while (op_node) {
    op_stack = op_node->next;
    op_node->next = filter_root;
    filter_root = op_node;
    op_node = op_stack;
  }
}

void find_main(void)
{
  /* parse filters, if present */
  build_filter_list();

  /* FIXTHIS - parse actions, if present */

  dirtree_read(TT.dir, check_node_callback);
}