output/ascii: data type nits, rephrase sample bit access

Use size types for counters, unsigned for bit manipulation. Trigger
position needs to remain a signed int (must be possible to go negative
for "not here", and strictly remains within the output text line length,
so should be good).

Rephrase the nested loop during bit extraction from logic packets, and
how a channel's value at a given sample number gets accessed. Eliminate
redundancy in that spot, to improve readability and simplify maintenance.

diff --git a/src/output/ascii.c b/src/output/ascii.c
index 7b3f878155594c58eb31cdf62a6e8da7abb4c2f6..ecab0fd152df4572edab424d7775eda1e978a36a 100644 (file)
--- a/src/output/ascii.c
+++ b/src/output/ascii.c
@@ -37,19 +37,18 @@
 #define DEFAULT_ASCII_CHARS ".\"\\/"
 
 struct context {
-       unsigned int num_enabled_channels;
-       int spl;
-       int spl_cnt;
+       size_t num_enabled_channels;
+       size_t spl;
+       size_t spl_cnt;
        int trigger;
        uint64_t samplerate;
        int *channel_index;
        char **aligned_names;
-       int max_namelen;
+       size_t max_namelen;
        char **line_values;
        uint8_t *prev_sample;
        gboolean header_done;
        GString **lines;
-       GString *header;
        const char *charset;
        gboolean edges;
 };
@@ -59,7 +58,7 @@ static int init(struct sr_output *o, GHashTable *options)
        struct context *ctx;
        struct sr_channel *ch;
        GSList *l;
-       unsigned int j, max_namelen, alloc_line_len;
+       size_t j, max_namelen, alloc_line_len;
 
        if (!o || !o->sdi)
                return SR_ERR_ARG;
@@ -111,7 +110,7 @@ static int init(struct sr_output *o, GHashTable *options)
                        continue;
 
                ctx->channel_index[j] = ch->index;
-               ctx->aligned_names[j] = g_strdup_printf("%*s", max_namelen, ch->name);
+               ctx->aligned_names[j] = g_strdup_printf("%*s", (int)max_namelen, ch->name);
 
                ctx->lines[j] = g_string_sized_new(alloc_line_len);
                g_string_printf(ctx->lines[j], "%s:", ctx->aligned_names[j]);
@@ -127,7 +126,7 @@ static GString *gen_header(const struct sr_output *o)
        struct context *ctx;
        GVariant *gvar;
        GString *header;
-       int num_channels;
+       size_t num_channels;
        char *samplerate_s;
 
        ctx = o->priv;
@@ -142,7 +141,7 @@ static GString *gen_header(const struct sr_output *o)
        header = g_string_sized_new(512);
        g_string_printf(header, "%s %s\n", PACKAGE_NAME, sr_package_version_string_get());
        num_channels = g_slist_length(o->sdi->channels);
-       g_string_append_printf(header, "Acquisition with %d/%d channels",
+       g_string_append_printf(header, "Acquisition with %zu/%zu channels",
                        ctx->num_enabled_channels, num_channels);
        if (ctx->samplerate != 0) {
                samplerate_s = sr_samplerate_string(ctx->samplerate);
@@ -158,7 +157,7 @@ static void maybe_add_trigger(struct context *ctx, GString *out)
 {
        int offset;
 
-       if (ctx->trigger <= -1)
+       if (ctx->trigger < 0)
                return;
        offset = ctx->trigger;
        ctx->trigger = -1;
@@ -169,11 +168,10 @@ static void maybe_add_trigger(struct context *ctx, GString *out)
         * to this layout.
         */
        g_string_append_printf(out, "%*s:%*s %d\n",
-               ctx->max_namelen, "T",
+               (int)ctx->max_namelen, "T",
                offset + 1, "^", offset);
 }
 
-
 static int receive(const struct sr_output *o, const struct sr_datafeed_packet *packet,
                GString **out)
 {
@@ -182,9 +180,12 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
        const struct sr_config *src;
        GSList *l;
        struct context *ctx;
-       int idx, curbit, prevbit;
-       uint64_t i, j;
-       gchar *p, c;
+       size_t idx, i, j;
+       size_t num_samples;
+       const uint8_t *curr_sample;
+       size_t bytepos;
+       uint8_t bitmask, curbit, prevbit;
+       char c;
        size_t charidx;
 
        *out = NULL;
@@ -215,13 +216,16 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
                }
 
                logic = packet->payload;
-               for (i = 0; i <= logic->length - logic->unitsize; i += logic->unitsize) {
+               num_samples = logic->length / logic->unitsize;
+               curr_sample = logic->data;
+               while (num_samples--) {
                        ctx->spl_cnt++;
                        for (j = 0; j < ctx->num_enabled_channels; j++) {
                                idx = ctx->channel_index[j];
-                               p = logic->data + i + idx / 8;
-                               curbit = *p & (1 << (idx % 8));
-                               prevbit = (ctx->prev_sample[idx / 8] & ((uint8_t) 1 << (idx % 8)));
+                               bytepos = idx / 8;
+                               bitmask = 1U << (idx % 8);
+                               curbit = curr_sample[bytepos] & bitmask;
+                               prevbit = ctx->prev_sample[bytepos] & bitmask;
 
                                charidx = curbit ? 1 : 0;
                                if (ctx->edges && ctx->spl_cnt > 1) {
@@ -235,7 +239,7 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
                                        /* Flush line buffers. */
                                        g_string_append_len(*out, ctx->lines[j]->str, ctx->lines[j]->len);
                                        g_string_append_c(*out, '\n');
-                                       if (j == ctx->num_enabled_channels - 1)
+                                       if (j + 1 == ctx->num_enabled_channels)
                                                maybe_add_trigger(ctx, *out);
                                        g_string_printf(ctx->lines[j], "%s:", ctx->aligned_names[j]);
                                }
@@ -243,7 +247,8 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
                        if (ctx->spl_cnt == ctx->spl)
                                /* Line buffers were already flushed. */
                                ctx->spl_cnt = 0;
-                       memcpy(ctx->prev_sample, logic->data + i, logic->unitsize);
+                       memcpy(ctx->prev_sample, curr_sample, logic->unitsize);
+                       curr_sample += logic->unitsize;
                }
                break;
        case SR_DF_END:
@@ -265,7 +270,7 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
 static int cleanup(struct sr_output *o)
 {
        struct context *ctx;
-       unsigned int i;
+       size_t i;
 
        if (!o)
                return SR_ERR_ARG;