summaryrefslogtreecommitdiff
path: root/libs/ardour/rdff.c
blob: ca8e1abf1fd6d07a155ea957c2cca4123188e7b6 (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
/*
  RDFF - RDF in RIFF
  Copyright 2011 David Robillard <http://drobilla.net>

  Permission to use, copy, modify, and/or distribute this software for any
  purpose with or without fee is hereby granted, provided that the above
  copyright notice and this permission notice appear in all copies.

  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "rdff.h"

#define CHUNK_ID_LEN 4

static const char FILE_TYPE[CHUNK_ID_LEN]  = "RDFF";  /* RDFF File ID */
static const char CHUNK_TRIP[CHUNK_ID_LEN] = "trip";  /* Triple Chunk ID */
static const char CHUNK_URID[CHUNK_ID_LEN] = "urid";  /* URI-ID Chunk ID*/

struct _RDFF {
	FILE*    fd;
	uint32_t size;
	bool     write;
};

RDFF
rdff_open(const char* path, bool write)
{
	FILE* fd = fopen(path, (write ? "w" : "r"));
	if (!fd) {
		fprintf(stderr, "%s\n", strerror(errno));
		return NULL;
	}

	uint32_t size = 0;

	if (write) {
		fwrite("RIFF", CHUNK_ID_LEN, 1, fd);    /* RIFF chunk ID */
		fwrite(&size, sizeof(size), 1, fd);     /* RIFF chunk size */
		fwrite(FILE_TYPE, CHUNK_ID_LEN, 1, fd); /* File type */
	} else {
		char magic[CHUNK_ID_LEN];
		if (fread(magic, CHUNK_ID_LEN, 1, fd) != 1
		    || strncmp(magic, "RIFF", CHUNK_ID_LEN)) {
			fclose(fd);
			fprintf(stderr, "%s: error: not a RIFF file\n", path);
			return NULL;
		}

		if (fread(&size, sizeof(size), 1, fd) != 1) {
			fclose(fd);
			fprintf(stderr, "%s: error: missing RIFF chunk size\n", path);
			return NULL;
		}

		if (fread(magic, CHUNK_ID_LEN, 1, fd) != 1
		    || strncmp(magic, FILE_TYPE, CHUNK_ID_LEN)) {
			fclose(fd);
			fprintf(stderr, "%s: error: not an %s RIFF file\n",
			        FILE_TYPE, path);
			return NULL;
		}
	}

	RDFF ret = (RDFF)malloc(sizeof(struct _RDFF));
	ret->fd    = fd;
	ret->size  = size;
	ret->write = write;
	return ret;
}

#define WRITE(ptr, size, nmemb, stream) \
	if (fwrite(ptr, size, nmemb, stream) != nmemb) { \
		return RDFF_STATUS_UNKNOWN_ERROR; \
	}

RDFFStatus
rdff_write_uri(RDFF        file,
               uint32_t    id,
               uint32_t    len,
               const char* uri)
{
	const uint32_t chunk_size = sizeof(id) + len + 1;
	WRITE(CHUNK_URID,  CHUNK_ID_LEN,       1, file->fd);
	WRITE(&chunk_size, sizeof(chunk_size), 1, file->fd);
	WRITE(&id,         sizeof(id),         1, file->fd);
	WRITE(uri,         len + 1,            1, file->fd);
	if ((chunk_size % 2)) {
		WRITE("", 1, 1, file->fd);  /* pad */
	}
	file->size += 8 + chunk_size;
	return RDFF_STATUS_OK;
}

RDFFStatus
rdff_write_triple(RDFF        file,
                  uint32_t    subject,
                  uint32_t    predicate,
                  uint32_t    object_type,
                  uint32_t    object_size,
                  const void* object)
{
	const uint32_t chunk_size = sizeof(RDFFTripleChunk) + object_size;
	WRITE(CHUNK_TRIP,   CHUNK_ID_LEN,        1, file->fd);
	WRITE(&chunk_size,  sizeof(chunk_size),  1, file->fd);
	WRITE(&subject,     sizeof(subject),     1, file->fd);
	WRITE(&predicate,   sizeof(predicate),   1, file->fd);
	WRITE(&object_type, sizeof(object_type), 1, file->fd);
	WRITE(&object_size, sizeof(object_size), 1, file->fd);
	WRITE(object,       object_size,         1, file->fd);
	if ((object_size % 2)) {
		WRITE("", 1, 1, file->fd);  /* write pad */
	}
	file->size += 8 + chunk_size;
	return RDFF_STATUS_OK;
}

RDFFStatus
rdff_read_chunk(RDFF        file,
                RDFFChunk** buf)
{
	if (feof(file->fd))
		return RDFF_STATUS_EOF;

#define READ(ptr, size, nmemb, stream) \
	if (fread(ptr, size, nmemb, stream) != nmemb) { \
		return RDFF_STATUS_CORRUPT; \
	}

	const uint32_t alloc_size = (*buf)->size;

	READ((*buf)->type,  sizeof((*buf)->type), 1, file->fd);
	READ(&(*buf)->size, sizeof((*buf)->size), 1, file->fd);
	if ((*buf)->size > alloc_size) {
		*buf = realloc(*buf, sizeof(RDFFChunk) + (*buf)->size);
	}
	READ((*buf)->data, (*buf)->size, 1, file->fd);
	if (((*buf)->size % 2)) {
		char pad;
		READ(&pad, 1, 1, file->fd);  /* skip pad */
	}
	return RDFF_STATUS_OK;
}

bool
rdff_chunk_is_uri(RDFFChunk* chunk)

{
	return !strncmp(chunk->type, CHUNK_URID, CHUNK_ID_LEN);
}

bool
rdff_chunk_is_triple(RDFFChunk* chunk)
{
	return !strncmp(chunk->type, CHUNK_TRIP, CHUNK_ID_LEN);
}

void
rdff_close(RDFF file)
{
	if (file) {
		if (file->write) {
			fseek(file->fd, 4, SEEK_SET);
			if (fwrite(&file->size, sizeof(file->size), 1, file->fd) != 1) {
				fprintf(stderr, "failed to write RIFF header size\n");
			}
		}
		fclose(file->fd);
	}

	free(file);
}

#ifdef STANDALONE
// Test program
int
main(int argc, char** argv)
{
	if (argc != 2) {
		fprintf(stderr, "Usage: %s FILENAME\n", argv[0]);
		return 1;
	}

	const char* const filename = argv[1];

	RDFF file = rdff_open(filename, true);
	if (!file)
		goto fail;

	static const int N_URIS    = 16;
	static const int N_RECORDS = 16;

	char uri[64];
	for (int i = 0; i < N_URIS; ++i) {
		snprintf(uri, sizeof(uri), "http://example.org/uri%02d", i + 1);
		rdff_write_uri(file, i + 1, strlen(uri), uri);
	}

	char val[6];
	for (int i = 0; i < N_RECORDS; ++i) {
		snprintf(val, sizeof(val), "VAL%02d", i);
		rdff_write_triple(file,
		                  0,
		                  rand() % N_URIS,
		                  0,
		                  sizeof(val),
		                  val);
	}

	rdff_close(file);

	file = rdff_open(filename, false);
	if (!file)
		goto fail;

	RDFFChunk* chunk = malloc(sizeof(RDFFChunk));
	chunk->size = 0;
	for (int i = 0; i < N_URIS; ++i) {
		if (rdff_read_chunk(file, &chunk)
		    || strncmp(chunk->type, CHUNK_URID, 4)) {
			fprintf(stderr, "error: expected %s chunk\n", CHUNK_URID);
			goto fail;
		}
		RDFFURIChunk* body = (RDFFURIChunk*)chunk->data;
		printf("URI: %s\n", body->uri);
	}

	for (int i = 0; i < N_RECORDS; ++i) {
		if (rdff_read_chunk(file, &chunk)
		    || strncmp(chunk->type, CHUNK_TRIP, 4)) {
			fprintf(stderr, "error: expected %s chunk\n", CHUNK_TRIP);
			goto fail;
		}
		RDFFTripleChunk* body = (RDFFTripleChunk*)chunk->data;
		printf("KEY %d = %s\n", body->predicate, body->object);
	}

	free(chunk);
	rdff_close(file);

	return 0;

fail:
	rdff_close(file);
	fprintf(stderr, "Test failed\n");
	return 1;
}
#endif // STANDALONE