2 * This file is part of the sigrok project.
4 * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
25 #include "sigrok-internal.h"
27 static gpointer new_chunk(struct sr_datastore **ds);
30 * Create a new datastore with the specified unit size.
32 * The unit size is fixed once the datastore is created, and cannot be
33 * changed later on, neither can data be added to the datastore with
34 * different unit sizes later.
36 * It is the caller's responsibility to free the allocated memory of the
37 * datastore via the sr_datastore_destroy() function, if no longer needed.
39 * TODO: Unitsize should probably be unsigned int or uint32_t or similar.
40 * TODO: This function should have a 'chunksize' parameter, and
41 * struct sr_datastore a 'chunksize' field.
43 * @param unitsize The unit size (>= 1) to be used for this datastore.
44 * @param ds Pointer to a variable which will hold the newly created
45 * datastore structure.
47 * @return SR_OK upon success, SR_ERR_MALLOC upon memory allocation errors,
48 * or SR_ERR_ARG upon invalid arguments. If something other than SR_OK
49 * is returned, the value of 'ds' is undefined.
51 SR_API int sr_datastore_new(int unitsize, struct sr_datastore **ds)
54 sr_err("ds: %s: ds was NULL", __func__);
59 sr_err("ds: %s: unitsize was %d, but it must be >= 1",
64 if (!(*ds = g_try_malloc(sizeof(struct sr_datastore)))) {
65 sr_err("ds: %s: ds malloc failed", __func__);
69 (*ds)->ds_unitsize = unitsize;
71 (*ds)->chunklist = NULL;
77 * Destroy the specified datastore and free the memory used by it.
79 * This will free the memory used by the data in the datastore's 'chunklist',
80 * by the chunklist data structure itself, and by the datastore struct.
82 * @param ds The datastore to destroy.
84 * @return SR_OK upon success, SR_ERR_ARG upon invalid arguments.
86 SR_API int sr_datastore_destroy(struct sr_datastore *ds)
91 sr_err("ds: %s: ds was NULL", __func__);
95 for (chunk = ds->chunklist; chunk; chunk = chunk->next)
97 g_slist_free(ds->chunklist);
100 /* TODO: Set ds = NULL? */
106 * Append some data to the specified datastore.
108 * TODO: More elaborate function description.
110 * TODO: This function should use the (not yet available) 'chunksize' field
111 * of struct sr_datastore (instead of hardcoding DATASTORE_CHUNKSIZE).
112 * TODO: in_unitsize and probelist are unused?
113 * TODO: A few of the parameters can be const.
114 * TODO: Handle new_chunk() returning NULL.
115 * TODO: Ideally, 'ds' should be unmodified upon errors.
117 * @param ds Pointer to the datastore which shall receive the data.
119 * @param data Pointer to the memory buffer containing the data to add.
120 * Must not be NULL. TODO: Data format?
121 * @param length Length of the data to add (in number of bytes).
122 * TODO: Should 0 be allowed as length?
123 * @param in_unitsize The unit size (>= 1) of the input data.
124 * @param probelist Pointer to a list of integers (probe numbers). The probe
125 * numbers in this list are 1-based, i.e. the first probe
126 * is expected to be numbered 1 (not 0!). Must not be NULL.
128 * @return SR_OK upon success, SR_ERR_MALLOC upon memory allocation errors,
129 * or SR_ERR_ARG upon invalid arguments. If something other than SR_OK
130 * is returned, the value/state of 'ds' is undefined.
132 SR_API int sr_datastore_put(struct sr_datastore *ds, void *data,
133 unsigned int length, int in_unitsize, int *probelist)
136 int capacity, size, num_chunks, chunk_bytes_free, chunk_offset;
139 /* Avoid compiler warnings. */
144 sr_err("ds: %s: ds was NULL", __func__);
148 /* Unitsize must not be 0, we'll divide by 0 otherwise. */
149 if (ds->ds_unitsize == 0) {
150 sr_err("ds: %s: ds->ds_unitsize was 0", __func__);
155 sr_err("ds: %s: data was NULL", __func__);
159 if (in_unitsize < 1) {
160 sr_err("ds: %s: in_unitsize was %d, but it must be >= 1",
161 __func__, in_unitsize);
166 sr_err("ds: %s: probelist was NULL", __func__);
170 /* Get the last chunk in the list, or create a new one if needed. */
171 if (ds->chunklist == NULL)
172 chunk = new_chunk(&ds);
174 chunk = g_slist_last(ds->chunklist)->data;
176 /* Get/calculate number of chunks, free space, etc. */
177 num_chunks = g_slist_length(ds->chunklist);
178 capacity = (num_chunks * DATASTORE_CHUNKSIZE);
179 chunk_bytes_free = capacity - (ds->ds_unitsize * ds->num_units);
180 chunk_offset = capacity - (DATASTORE_CHUNKSIZE * (num_chunks - 1))
184 while (stored < length) {
185 /* No more free space left, allocate a new chunk. */
186 if (chunk_bytes_free == 0) {
187 chunk = new_chunk(&ds);
188 chunk_bytes_free = DATASTORE_CHUNKSIZE;
192 if (length - stored > (unsigned int)chunk_bytes_free)
193 size = chunk_bytes_free;
195 /* Last part, won't fill up this chunk. */
196 size = length - stored;
198 memcpy(chunk + chunk_offset, data + stored, size);
199 chunk_bytes_free -= size;
203 ds->num_units += stored / ds->ds_unitsize;
209 * Allocate a new memory chunk, append it to the datastore's chunklist.
211 * The newly allocated chunk is added to the datastore's chunklist by this
212 * function, and the return value additionally points to the new chunk.
214 * The allocated memory is guaranteed to be cleared.
216 * TODO: This function should use the datastore's 'chunksize' field instead
217 * of hardcoding DATASTORE_CHUNKSIZE.
218 * TODO: Return int, so we can return SR_OK / SR_ERR_ARG / SR_ERR_MALLOC?
220 * @param ds Pointer to a variable which holds the datastore structure.
221 * Must not be NULL. The contents of 'ds' are modified in-place.
223 * @return Pointer to the newly allocated chunk, or NULL upon failure.
225 static gpointer new_chunk(struct sr_datastore **ds)
230 sr_err("ds: %s: ds was NULL", __func__);
231 return NULL; /* TODO: SR_ERR_ARG later? */
234 chunk = g_try_malloc0(DATASTORE_CHUNKSIZE * (*ds)->ds_unitsize);
236 sr_err("ds: %s: chunk malloc failed", __func__);
237 return NULL; /* TODO: SR_ERR_MALLOC later? */
240 (*ds)->chunklist = g_slist_append((*ds)->chunklist, chunk);
242 return chunk; /* TODO: SR_OK later? */