input/csv: improve "channel name from header line" logic

Improve the code paths which determine logic channels' names from an
optional CSV file header line. Strip optional quotes from the column's
input text (re-use a SCPI helper routine for that). Also use the channel
name for multi-bit fields, append [0] etc suffixes in that case. Comment
on the manipulation of input data, which is acceptable since that very
data won't get processed another time in another code path.

diff --git a/src/input/csv.c b/src/input/csv.c
index 0833f3182dad07658380c0a9923ecae667e198c5..17c253a29d2f29aff5c3cabc6397da1d1fbfecc0 100644 (file)
--- a/src/input/csv.c
+++ b/src/input/csv.c
@@ -26,6 +26,7 @@
 
 #include <libsigrok/libsigrok.h>
 #include "libsigrok-internal.h"
+#include "scpi.h"      /* String un-quote for channel name from header line. */
 
 #define LOG_PREFIX "input/csv"
 
@@ -666,6 +667,8 @@ static int initial_parse(const struct sr_input *in, GString *buf)
        size_t line_number, line_idx;
        int ret;
        char **lines, *line, **columns, *column;
+       const char *col_caption;
+       gboolean got_caption;
        const struct column_details *detail;
 
        ret = SR_OK;
@@ -744,20 +747,29 @@ static int initial_parse(const struct sr_input *in, GString *buf)
         * line (when requested by the user, and only works in multi
         * column mode). In the absence of header text, or in single
         * column mode, channels are assigned rather generic names.
+        *
+        * Manipulation of the column's caption is acceptable here, the
+        * header line will never get processed another time.
         */
        channel_name = g_string_sized_new(64);
        for (col_idx = 0; col_idx < inc->column_want_count; col_idx++) {
+
                col_nr = col_idx + 1;
                detail = lookup_column_details(inc, col_nr);
                if (detail->text_format == FORMAT_NONE)
                        continue;
                column = columns[col_idx];
+               col_caption = sr_scpi_unquote_string(column);
+               got_caption = inc->use_header && *col_caption;
                sr_dbg("DIAG col %zu, ch count %zu, text %s.",
-                       col_nr, detail->channel_count, column);
+                       col_nr, detail->channel_count, col_caption);
                for (ch_idx = 0; ch_idx < detail->channel_count; ch_idx++) {
                        ch_name_idx = detail->channel_offset + ch_idx;
-                       if (inc->use_header && *column && inc->multi_column_mode)
-                               g_string_assign(channel_name, column);
+                       if (got_caption && detail->channel_count == 1)
+                               g_string_assign(channel_name, col_caption);
+                       else if (got_caption)
+                               g_string_printf(channel_name, "%s[%zu]",
+                                       col_caption, ch_idx);
                        else
                                g_string_printf(channel_name, "%zu", ch_name_idx);
                        sr_dbg("DIAG ch idx %zu, name %s.", ch_name_idx, channel_name->str);