fix buffer size, various error checks

diff --git a/output/output_gnuplot.c b/output/output_gnuplot.c
index 5d4c564b1071e646f8f9e7c13875b6247f269ca4..51648c4475be90b85a7183d677c13869381bc072 100644 (file)
--- a/output/output_gnuplot.c
+++ b/output/output_gnuplot.c
@@ -27,15 +27,16 @@
 struct context {
        unsigned int num_enabled_probes;
        unsigned int unitsize;
-       char *probelist[65];
+       char *probelist[MAX_NUM_PROBES+1];
        char *header;
 };
 
+#define MAX_HEADER_LEN   1024 + (MAX_NUM_PROBES * (MAX_PROBENAME_LEN + 10))
 const char *gnuplot_header = "\
 # Sample data in space-separated columns format usable by gnuplot\n\
 #\n\
 # Generated by: %s on %s%s\
-# Timescale: %d %s\n\
+# Period: %s\n\
 #\n\
 # Column\tProbe\n\
 # -------------------------------------\
@@ -47,22 +48,24 @@ const char *gnuplot_header_comment = "\
 
 static int init(struct output *o)
 {
-/* Maximum header length */
-#define MAX_HEADER_LEN 2048
-
        struct context *ctx;
        struct probe *probe;
        GSList *l;
        uint64_t samplerate;
        unsigned int i;
        int b, num_probes;
-       char *c, *samplerate_s;
+       char *c, *frequency_s;
        char wbuf[1000], comment[128];
        time_t t;
 
        if (!(ctx = calloc(1, sizeof(struct context))))
                return SIGROK_ERR_MALLOC;
 
+       if (!(ctx->header = calloc(1, MAX_HEADER_LEN + 1))) {
+               free(ctx);
+               return SIGROK_ERR_MALLOC;
+       }
+
        o->internal = ctx;
        ctx->num_enabled_probes = 0;
        for (l = o->device->probes; l; l = l->next) {
@@ -71,32 +74,22 @@ static int init(struct output *o)
                        continue;
                ctx->probelist[ctx->num_enabled_probes++] = probe->name;
        }
-
        ctx->probelist[ctx->num_enabled_probes] = 0;
        ctx->unitsize = (ctx->num_enabled_probes + 7) / 8;
 
-       /* TODO: Allow for configuration via o->param. */
-
-       if (!(ctx->header = calloc(1, MAX_HEADER_LEN + 1))) {
-               free(ctx);
-               return SIGROK_ERR_MALLOC;
-       }
-
        num_probes = g_slist_length(o->device->probes);
-       /* TODO: Handle num_probes == 0, too many probes, etc. */
-
        comment[0] = '\0';
        if (o->device->plugin) {
                samplerate = *((uint64_t *) o->device->plugin->get_device_info(
                                o->device->plugin_index, DI_CUR_SAMPLERATE));
-               if (!(samplerate_s = sigrok_samplerate_string(samplerate))) {
+               if (!(frequency_s = sigrok_samplerate_string(samplerate))) {
                        free(ctx->header);
                        free(ctx);
                        return SIGROK_ERR;
                }
                snprintf(comment, 127, gnuplot_header_comment,
-                        ctx->num_enabled_probes, num_probes, samplerate_s);
-               free(samplerate_s);
+                       ctx->num_enabled_probes, num_probes, frequency_s);
+               free(frequency_s);
        }
 
        /* Columns / channels */
@@ -106,14 +99,22 @@ static int init(struct output *o)
                sprintf(c, "# %d\t\t%s\n", i + 1, ctx->probelist[i]);
        }
 
-       /* TODO: date: File or signals? Make y/n configurable. */
-       /* TODO: Timescale */
+       if (!(frequency_s = sigrok_period_string(samplerate))) {
+               free(ctx->header);
+               free(ctx);
+               return SIGROK_ERR;
+       }
        t = time(NULL);
        b = snprintf(ctx->header, MAX_HEADER_LEN, gnuplot_header,
-                    PACKAGE_STRING, ctime(&t), comment, 1, "ns",
+                    PACKAGE_STRING, ctime(&t), comment, frequency_s,
                     (char *)&wbuf);
+       free(frequency_s);
 
-       /* TODO: Handle snprintf errors. */
+       if (b < 0) {
+               free(ctx->header);
+               free(ctx);
+               return SIGROK_ERR;
+       }
 
        return 0;
 }
@@ -143,19 +144,19 @@ static int data(struct output *o, char *data_in, uint64_t length_in,
                char **data_out, uint64_t *length_out)
 {
        struct context *ctx;
-       unsigned int i, outsize, p, curbit;
+       unsigned int max_linelen, outsize, p, curbit, i;
        uint64_t sample;
        static uint64_t samplecount = 0;
        char *outbuf, *c;
 
        ctx = o->internal;
-       outsize = 0;
+       max_linelen = 16 + ctx->num_enabled_probes * 2;
+       outsize = length_in / ctx->unitsize * max_linelen;
        if (ctx->header)
-               outsize = strlen(ctx->header);
+               outsize += strlen(ctx->header);
 
-       /* FIXME: Use realloc(). */
-       if (!(outbuf = calloc(1, outsize + 1 + 1000000)))
-               return SIGROK_ERR_MALLOC; /* TODO: free()? What to free? */
+       if (!(outbuf = calloc(1, outsize)))
+               return SIGROK_ERR_MALLOC;
 
        outbuf[0] = '\0';
        if (ctx->header) {
@@ -165,14 +166,12 @@ static int data(struct output *o, char *data_in, uint64_t length_in,
                ctx->header = NULL;
        }
 
-       /* TODO: Are disabled probes handled correctly? */
-
        for (i = 0; i <= length_in - ctx->unitsize; i += ctx->unitsize) {
                memcpy(&sample, data_in + i, ctx->unitsize);
 
                /* The first column is a counter (needed for gnuplot). */
                c = outbuf + strlen(outbuf);
-               sprintf(c, "%" PRIu64 "\t\t", samplecount++);
+               sprintf(c, "%" PRIu64 "\t", samplecount++);
 
                /* The next columns are the values of all channels. */
                for (p = 0; p < ctx->num_enabled_probes; p++) {
@@ -183,8 +182,6 @@ static int data(struct output *o, char *data_in, uint64_t length_in,
 
                c = outbuf + strlen(outbuf);
                sprintf(c, "\n");
-
-               /* TODO: realloc() if strlen(outbuf) is almost "full"... */
        }
 
        *data_out = outbuf;