Merge remote-tracking branch 'upstream/dev' into statsd_stack

esphome/components/statsd/statsd.cpp

@@ -114,14 +114,23 @@ void StatsdComponent::update() {
     // This implies you can't explicitly set a gauge to a negative number without first setting it to zero.
     if (val < 0) {
       if (this->prefix_) {
-        out.append(str_sprintf("%s.", this->prefix_));
+        out.append(this->prefix_);
+        out.append(".");
       }
-      out.append(str_sprintf("%s:0|g\n", s.name));
+      out.append(s.name);
+      out.append(":0|g\n");
     }
     if (this->prefix_) {
-      out.append(str_sprintf("%s.", this->prefix_));
+      out.append(this->prefix_);
+      out.append(".");
     }
-    out.append(str_sprintf("%s:%f|g\n", s.name, val));
+    out.append(s.name);
+    // Buffer for ":" + value + "|g\n".
+    // %g uses max 13 chars for value (sign + 6 significant digits + e+xxx)
+    // Total: 1 + 13 + 4 = 18 chars + null, use 24 for safety
+    char val_buf[24];
+    buf_append_printf(val_buf, sizeof(val_buf), 0, ":%g|g\n", val);
+    out.append(val_buf);
 
     if (out.length() > SEND_THRESHOLD) {
       this->send_(&out);

esphome/components/syslog/esphome_syslog.cpp

@@ -47,27 +47,29 @@ void Syslog::log_(const int level, const char *tag, const char *message, size_t
   size_t remaining = sizeof(packet);
 
   // Write PRI - abort if this fails as packet would be malformed
-  offset = buf_append_printf(packet, sizeof(packet), 0, "<%d>", pri);
-  if (offset == 0) {
-    return;  // PRI always produces at least "<0>" (3 chars), so 0 means error
+  int ret = snprintf(packet, remaining, "<%d>", pri);
+  if (ret <= 0 || static_cast<size_t>(ret) >= remaining) {
+    return;
   }
-  remaining -= offset;
+  offset = ret;
+  remaining -= ret;
 
   // Write timestamp directly into packet (RFC 5424: use "-" if time not valid or strftime fails)
   auto now = this->time_->now();
   size_t ts_written = now.is_valid() ? now.strftime(packet + offset, remaining, "%b %e %H:%M:%S") : 0;
   if (ts_written > 0) {
     offset += ts_written;
+    remaining -= ts_written;
   } else if (remaining > 0) {
     packet[offset++] = '-';
+    remaining--;
   }
 
   // Write hostname, tag, and message
-  offset = buf_append_printf(packet, sizeof(packet), offset, " %s %s: %.*s", App.get_name().c_str(), tag, (int) len,
-                             message);
-  // Clamp to exclude null terminator position if buffer was filled
-  if (offset >= sizeof(packet)) {
-    offset = sizeof(packet) - 1;
+  ret = snprintf(packet + offset, remaining, " %s %s: %.*s", App.get_name().c_str(), tag, (int) len, message);
+  if (ret > 0) {
+    // snprintf returns chars that would be written; clamp to actual buffer space
+    offset += std::min(static_cast<size_t>(ret), remaining > 0 ? remaining - 1 : 0);
   }
 
   if (offset > 0) {