From: Bert Vermeulen <redacted>
Date: Sat, 8 Jan 2011 14:48:39 +0000 (+0100)
Subject: fix buffer size, various error checks
X-Git-Tag: libsigrok-0.1.0~471
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=d4ae8eaa7c09e31ef246b7d56008a0aa21db9f0d;p=libsigrok.git

fix buffer size, various error checks
---

diff --git a/output/output_gnuplot.c b/output/output_gnuplot.c
index 5d4c564b..51648c44 100644
--- 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;