Improve some strcpy strncpy to snprintf

src/abuf.c

@@ -45,7 +45,7 @@ void abuf_cat(abuf_t *buf, char const *str)
 {
     size_t len = strlen(str);
     if (buf->left >= len + 1) {
-        strcpy(buf->tail, str);
+        memcpy(buf->tail, str, len + 1);
         buf->tail += len;
         buf->left -= len;
     }

src/data_tag.c

@@ -42,7 +42,7 @@ char const filter_nmea[] = "$GPGGA,";
 static void gpsd_client_line(gpsd_client_t *ctx, char *line)
 {
     if (!ctx->filter_str || strncmp(line, ctx->filter_str, strlen(ctx->filter_str)) == 0) {
-        strncpy(ctx->msg, line, sizeof(ctx->msg) - 1);
+        snprintf(ctx->msg, sizeof(ctx->msg), "%s", line);
     }
 }
 
@@ -263,7 +263,6 @@ static data_t *append_filtered_json(data_t *data, char const *json, char const *
     }
 
     // check all tokens
-    char buf[1024] = {0};
     for (int i = 1; i < toks - 1; ++i) {
         jsmntok_t *k = tok + i;
         jsmntok_t *v = tok + i + 1;
@@ -276,7 +275,10 @@ static data_t *append_filtered_json(data_t *data, char const *json, char const *
         char const *key = find_list_strncmp(includes, json + k->start, k->end - k->start);
         if (key) {
             // append json tag
-            strncpy(buf, json + v->start, v->end - v->start);
+            char buf[1024];
+            int len = MIN(v->end - v->start, (int)sizeof(buf) - 1);
+            memcpy(buf, json + v->start, len);
+            buf[len] = '\0';
             data = data_append(data,
                     key, "", DATA_STRING, buf,
                     NULL);

src/devices/simplisafe.c

@@ -69,13 +69,15 @@ static int ss_sensor_parser(r_device *decoder, bitbuffer_t *bitbuffer, int row)
     char id[6];
     ss_get_id(id, b);
 
-    char extradata[30] = "";
+    char extradata[30];
     if (state == 1) {
-        strncpy(extradata, "Contact Open", sizeof(extradata) - 1);
+        snprintf(extradata, sizeof(extradata), "Contact Open");
     } else if (state == 2) {
-        strncpy(extradata, "Contact Closed", sizeof(extradata) - 1);
+        snprintf(extradata, sizeof(extradata), "Contact Closed");
     } else if (state == 3) {
-        strncpy(extradata, "Alarm Off", sizeof(extradata) - 1);
+        snprintf(extradata, sizeof(extradata), "Alarm Off");
+    } else {
+        snprintf(extradata, sizeof(extradata), "");
     }
 
     /* clang-format off */
@@ -139,15 +141,15 @@ static int ss_keypad_commands(r_device *decoder, bitbuffer_t *bitbuffer, int row
     char extradata[30]; // = "Arming: ";
 
     if (b[10] == 0x6a) {
-        strncpy(extradata, "Arm System - Away", sizeof(extradata) - 1);
+        snprintf(extradata, sizeof(extradata), "Arm System - Away");
     } else if (b[10] == 0xca) {
-        strncpy(extradata, "Arm System - Home", sizeof(extradata) - 1);
+        snprintf(extradata, sizeof(extradata), "Arm System - Home");
     } else if (b[10] == 0x3a) {
-        strncpy(extradata, "Arm System - Canceled", sizeof(extradata) - 1);
+        snprintf(extradata, sizeof(extradata), "Arm System - Canceled");
     } else if (b[10] == 0x2a) {
-        strncpy(extradata, "Keypad Panic Button", sizeof(extradata) - 1);
+        snprintf(extradata, sizeof(extradata), "Keypad Panic Button");
     } else if (b[10] == 0x86) {
-        strncpy(extradata, "Keypad Menu Button", sizeof(extradata) - 1);
+        snprintf(extradata, sizeof(extradata), "Keypad Menu Button");
     } else {
         snprintf(extradata, sizeof(extradata), "Unknown Keypad: %02x", b[10]);
     }

src/output_influx.c

@@ -91,8 +91,7 @@ static void influx_client_event(struct mg_connection *nc, int ev, void *ev_data)
 
 static influx_client_t *influx_client_init(influx_client_t *ctx, char const *url, char const *token)
 {
-    strncpy(ctx->url, url, sizeof(ctx->url));
-    ctx->url[sizeof(ctx->url) - 1] = '\0';
+    snprintf(ctx->url, sizeof(ctx->url), "%s", url);
     snprintf(ctx->extra_headers, sizeof (ctx->extra_headers), "Authorization: Token %s\r\n", token);
 
     return ctx;

src/output_mqtt.c

@@ -115,8 +115,7 @@ static mqtt_client_t *mqtt_client_init(struct mg_mgr *mgr, tls_opts_t *tls_opts,
     //ctx->opts.keepalive = 60;
     //ctx->timeout = 10000L;
     //ctx->cleansession = 1;
-    strncpy(ctx->client_id, client_id, sizeof(ctx->client_id));
-    ctx->client_id[sizeof(ctx->client_id) - 1] = '\0';
+    snprintf(ctx->client_id, sizeof(ctx->client_id), "%s", client_id);
 
     // if the host is an IPv6 address it needs quoting
     if (strchr(host, ':'))

src/sdr.c

@@ -139,9 +139,9 @@ static int rtltcp_open(sdr_dev_t **out_dev, char const *dev_query, int verbose)
 
     char *param = arg_param(dev_query); // strip scheme
     hostport[0] = '\0';
-    if (param)
-        strncpy(hostport, param, sizeof(hostport) - 1);
-    hostport[sizeof(hostport) - 1] = '\0';
+    if (param) {
+        snprintf(hostport, sizeof(hostport), "%s", param);
+    }
     hostport_param(hostport, &host, &port);
 
     print_logf(LOG_CRITICAL, "SDR", "rtl_tcp input from %s port %s", host, port);
@@ -720,8 +720,7 @@ static int soapysdr_gain_str_set(SoapySDRDevice *dev, char const *gain_str, int
 
     if (strchr(gain_str, '=')) {
         char gain_cpy[GAIN_STR_MAX_SIZE];
-        strncpy(gain_cpy, gain_str, GAIN_STR_MAX_SIZE);
-        gain_cpy[GAIN_STR_MAX_SIZE - 1] = '\0';
+        snprintf(gain_cpy, sizeof(gain_cpy), "%s", gain_str);
         char *gain_p = gain_cpy;
         // Set each gain individually (more control)
         char *name;