#define LOG_PREFIX "input/csv"
+#define DATAFEED_MAX_SAMPLES (128 * 1024)
+
/*
* The CSV input module has the following options:
*
* than 0. The default line number to start processing is 1.
*/
+/*
+ * TODO
+ *
+ * - Determine how the text line handling can get improved, regarding
+ * all of robustness and flexibility and correctness.
+ * - The current implementation splits on "any run of CR and LF". Which
+ * translates to: Line numbers are wrong in the presence of empty
+ * lines in the input stream. See below for an (expensive) fix.
+ * - Dropping support for CR style end-of-line markers could improve
+ * the situation a lot. Code could search for and split on LF, and
+ * trim optional trailing CR. This would result in proper support
+ * for CRLF (Windows) as well as LF (Unix), and allow for correct
+ * line number counts.
+ * - When support for CR-only line termination cannot get dropped,
+ * then the current implementation is inappropriate. Currently the
+ * input stream is scanned for the first occurance of either of the
+ * supported termination styles (which is good). For the remaining
+ * session a consistent encoding of the text lines is assumed (which
+ * is acceptable).
+ * - When line numbers need to be correct and reliable, _and_ the full
+ * set of previously supported line termination sequences are required,
+ * and potentially more are to get added for improved compatibility
+ * with more platforms or generators, then the current approach of
+ * splitting on runs of termination characters needs to get replaced,
+ * by the more expensive approach to scan for and count the initially
+ * determined termination sequence.
+ *
+ * - Add support for analog input data? (optional)
+ * - Needs a syntax first for user specs which channels (columns) are
+ * logic and which are analog. May need heuristics(?) to guess from
+ * input data in the absence of user provided specs.
+ */
+
/* Single column formats. */
enum {
FORMAT_BIN,
/* Format sample data is stored in single column mode. */
int format;
- /* Size of the sample buffer. */
- size_t sample_buffer_size;
+ size_t sample_unit_size; /**!< Byte count for a single sample. */
+ uint8_t *sample_buffer; /**!< Buffer for a single sample. */
- /* Buffer to store sample data. */
- uint8_t *sample_buffer;
+ uint8_t *datafeed_buffer; /**!< Queue for datafeed submission. */
+ size_t datafeed_buf_size;
+ size_t datafeed_buf_fill;
/* Current line number. */
size_t line_number;
}
/* Clear buffer in order to set bits only. */
- memset(inc->sample_buffer, 0, (inc->num_channels + 7) >> 3);
+ memset(inc->sample_buffer, 0, inc->sample_unit_size);
i = inc->first_channel;
}
/* Clear buffer in order to set bits only. */
- memset(inc->sample_buffer, 0, (inc->num_channels + 7) >> 3);
+ memset(inc->sample_buffer, 0, inc->sample_unit_size);
/* Calculate the position of the first hexadecimal digit. */
i = inc->first_channel / 4;
}
/* Clear buffer in order to set bits only. */
- memset(inc->sample_buffer, 0, (inc->num_channels + 7) >> 3);
+ memset(inc->sample_buffer, 0, inc->sample_unit_size);
/* Calculate the position of the first octal digit. */
i = inc->first_channel / 3;
char *column;
/* Clear buffer in order to set bits only. */
- memset(inc->sample_buffer, 0, (inc->num_channels + 7) >> 3);
+ memset(inc->sample_buffer, 0, inc->sample_unit_size);
for (i = 0; i < inc->num_channels; i++) {
column = columns[i];
return res;
}
-static int send_samples(const struct sr_dev_inst *sdi, uint8_t *buffer,
- gsize buffer_size, gsize count)
+static int flush_samples(const struct sr_input *in)
{
+ struct context *inc;
struct sr_datafeed_packet packet;
struct sr_datafeed_logic logic;
- int res;
- gsize i;
+ int rc;
+
+ inc = in->priv;
+ if (!inc->datafeed_buf_fill)
+ return SR_OK;
+ memset(&packet, 0, sizeof(packet));
+ memset(&logic, 0, sizeof(logic));
packet.type = SR_DF_LOGIC;
packet.payload = &logic;
- logic.unitsize = buffer_size;
- logic.length = buffer_size;
- logic.data = buffer;
-
- for (i = 0; i < count; i++) {
- res = sr_session_send(sdi, &packet);
- if (res != SR_OK)
- return res;
- }
+ logic.unitsize = inc->sample_unit_size;
+ logic.length = inc->datafeed_buf_fill;
+ logic.data = inc->datafeed_buffer;
+
+ rc = sr_session_send(in->sdi, &packet);
+ if (rc != SR_OK)
+ return rc;
+
+ inc->datafeed_buf_fill = 0;
+ return SR_OK;
+}
+
+static int queue_samples(const struct sr_input *in)
+{
+ struct context *inc;
+ int rc;
+ inc = in->priv;
+
+ inc->datafeed_buf_fill += inc->sample_unit_size;
+ if (inc->datafeed_buf_fill == inc->datafeed_buf_size) {
+ rc = flush_samples(in);
+ if (rc != SR_OK)
+ return rc;
+ }
+ inc->sample_buffer = &inc->datafeed_buffer[inc->datafeed_buf_fill];
return SR_OK;
}
g_string_free(channel_name, TRUE);
/*
- * Calculate the minimum buffer size to store the sample data of the
- * channels.
+ * Calculate the minimum buffer size to store the set of samples
+ * of all channels (unit size). Determine a larger buffer size
+ * for datafeed submission that is a multiple of the unit size.
+ * Allocate the larger buffer, and have the "sample buffer" point
+ * to a location within that large buffer.
*/
- inc->sample_buffer_size = (inc->num_channels + 7) >> 3;
- inc->sample_buffer = g_malloc(inc->sample_buffer_size);
+ inc->sample_unit_size = (inc->num_channels + 7) / 8;
+ inc->datafeed_buf_size = DATAFEED_MAX_SAMPLES;
+ inc->datafeed_buf_size *= inc->sample_unit_size;
+ inc->datafeed_buffer = g_malloc(inc->datafeed_buf_size);
+ inc->datafeed_buf_fill = 0;
+ inc->sample_buffer = &inc->datafeed_buffer[inc->datafeed_buf_fill];
out:
if (columns)
return ret;
}
+/*
+ * Gets called from initial_receive(), which runs until the end-of-line
+ * encoding of the input stream could get determined. Assumes that this
+ * routine receives enough buffered initial input data to either see the
+ * BOM when there is one, or that no BOM will follow when a text line
+ * termination sequence was seen. Silently drops the UTF-8 BOM sequence
+ * from the input buffer if one was seen. Does not care to protect
+ * against multiple execution or dropping the BOM multiple times --
+ * there should be at most one in the input stream.
+ */
+static void initial_bom_check(const struct sr_input *in)
+{
+ static const char *utf8_bom = "\xef\xbb\xbf";
+
+ if (in->buf->len < strlen(utf8_bom))
+ return;
+ if (strncmp(in->buf->str, utf8_bom, strlen(utf8_bom)) != 0)
+ return;
+ g_string_erase(in->buf, 0, strlen(utf8_bom));
+}
+
static int initial_receive(const struct sr_input *in)
{
struct context *inc;
char *p;
const char *termination;
+ initial_bom_check(in);
+
inc = in->priv;
termination = get_line_termination(in->buf);
return ret;
}
-static int process_buffer(struct sr_input *in)
+static int process_buffer(struct sr_input *in, gboolean is_eof)
{
struct sr_datafeed_packet packet;
struct sr_datafeed_meta meta;
* maximum amount of accumulated data that consists of full text
* lines, and process what has been received so far, leaving not
* yet complete lines for the next invocation.
+ *
+ * Enforce that all previously buffered data gets processed in
+ * the "EOF" condition. Do not insist in the presence of the
+ * termination sequence for the last line (may often be missing
+ * on Windows). A present termination sequence will just result
+ * in the "execution of an empty line", and does not harm.
*/
if (!in->buf->len)
return SR_OK;
- p = g_strrstr_len(in->buf->str, in->buf->len, inc->termination);
- if (!p)
- return SR_ERR;
- *p = '\0';
+ if (is_eof) {
+ p = in->buf->str + in->buf->len;
+ } else {
+ p = g_strrstr_len(in->buf->str, in->buf->len, inc->termination);
+ if (!p)
+ return SR_ERR;
+ *p = '\0';
+ p += strlen(inc->termination);
+ }
g_strstrip(in->buf->str);
ret = SR_OK;
columns = parse_line(line, inc, max_columns);
if (!columns) {
sr_err("Error while parsing line %zu.", inc->line_number);
+ g_strfreev(lines);
return SR_ERR;
}
num_columns = g_strv_length(columns);
sr_err("Column %u in line %zu is out of bounds.",
inc->first_column, inc->line_number);
g_strfreev(columns);
+ g_strfreev(lines);
return SR_ERR;
}
/*
sr_err("Not enough columns for desired number of channels in line %zu.",
inc->line_number);
g_strfreev(columns);
+ g_strfreev(lines);
return SR_ERR;
}
ret = parse_single_column(columns[0], inc);
if (ret != SR_OK) {
g_strfreev(columns);
+ g_strfreev(lines);
return SR_ERR;
}
/* Send sample data to the session bus. */
- ret = send_samples(in->sdi, inc->sample_buffer,
- inc->sample_buffer_size, 1);
+ ret = queue_samples(in);
if (ret != SR_OK) {
sr_err("Sending samples failed.");
+ g_strfreev(columns);
+ g_strfreev(lines);
return SR_ERR;
}
+
g_strfreev(columns);
}
g_strfreev(lines);
- g_string_erase(in->buf, 0, p - in->buf->str + 1);
+ g_string_erase(in->buf, 0, p - in->buf->str);
return ret;
}
return SR_OK;
}
- ret = process_buffer(in);
+ ret = process_buffer(in, FALSE);
return ret;
}
int ret;
if (in->sdi_ready)
- ret = process_buffer(in);
+ ret = process_buffer(in, TRUE);
else
ret = SR_OK;
+ if (ret != SR_OK)
+ return ret;
+
+ ret = flush_samples(in);
+ if (ret != SR_OK)
+ return ret;
inc = in->priv;
if (inc->started)
g_string_free(inc->comment, TRUE);
g_free(inc->termination);
- g_free(inc->sample_buffer);
+ g_free(inc->datafeed_buffer);
}
static int reset(struct sr_input *in)
projects / libsigrok.git / blobdiff