Optimize startup, HTTP/SSE streaming, and fix macOS libedit bindings

util.cpp

@@ -12,11 +12,15 @@
 
 /* ----------------------------- formatting ----------------------------- */
 static std::string vfmt(const char *fmt, va_list ap) {
+  char stack_buf[512];
   va_list cp;
   va_copy(cp, ap);
-  int need = std::vsnprintf(nullptr, 0, fmt, cp);
+  int need = std::vsnprintf(stack_buf, sizeof stack_buf, fmt, cp);
   va_end(cp);
   if (need < 0) return {};
+  if ((size_t)need < sizeof stack_buf) {
+    return std::string(stack_buf, (size_t)need);
+  }
   std::string s;
   s.resize((size_t)need);
   std::vsnprintf(s.data(), (size_t)need + 1, fmt, ap);
@@ -30,11 +34,22 @@ std::string sfmt(const char *fmt, ...) {
   return s;
 }
 void str_appendf(std::string &s, const char *fmt, ...) {
-  va_list ap;
+  char stack_buf[512];
+  va_list ap, cp;
   va_start(ap, fmt);
-  std::string more = vfmt(fmt, ap);
+  va_copy(cp, ap);
+  int need = std::vsnprintf(stack_buf, sizeof stack_buf, fmt, cp);
+  va_end(cp);
+  if (need > 0) {
+    if ((size_t)need < sizeof stack_buf) {
+      s.append(stack_buf, (size_t)need);
+    } else {
+      size_t old_sz = s.size();
+      s.resize(old_sz + (size_t)need);
+      std::vsnprintf(s.data() + old_sz, (size_t)need + 1, fmt, ap);
+    }
+  }
   va_end(ap);
-  s += more;
 }
 
 /* ----------------------------- UTF-8 ---------------------------------- */
@@ -102,6 +117,19 @@ std::string filter_text(std::string_view s) {
   const unsigned char *p = (const unsigned char *)s.data();
   size_t avail = s.size();
   while (avail > 0) {
+    /* Fast path: scan contiguous printable ASCII plus '\t' and '\n'. */
+    size_t run = 0;
+    while (run < avail) {
+      unsigned char b = p[run];
+      if ((b >= 0x20 && b <= 0x7e) || b == '\n' || b == '\t') run++;
+      else break;
+    }
+    if (run > 0) {
+      out.append((const char *)p, run);
+      p += run;
+      avail -= run;
+      if (avail == 0) break;
+    }
     size_t pl;
     int cp = utf8_decode(p, avail, &pl);
     if (cp == 0xFFFD && pl == 1) { p++; avail--; continue; }
@@ -183,10 +211,12 @@ int rune_width(int cp) {
 void mkdir_p(std::string_view dir) {
   if (dir.empty()) return;
   std::string path(dir);
+  struct stat st;
+  if (stat(path.c_str(), &st) == 0 && S_ISDIR(st.st_mode)) return;
   for (size_t i = 1; i < path.size(); i++) {
     if (path[i] == '/') {
       path[i] = '\0';
-      mkdir(path.c_str(), 0755);
+      if (stat(path.c_str(), &st) != 0) mkdir(path.c_str(), 0755);
       path[i] = '/';
     }
   }
@@ -218,12 +248,15 @@ std::string tool_res_dir(std::string_view sess_id) {
   return p;
 }
 std::string project_id() {
-  char cwd[4096];
-  if (!getcwd(cwd, sizeof cwd)) std::strcpy(cwd, ".");
-  char *abs = realpath(cwd, nullptr);
-  std::string src = abs ? abs : cwd;
-  if (abs) free(abs);
-  return md5_hex(src);
+  static const std::string cached_id = []() {
+    char cwd[4096];
+    if (!getcwd(cwd, sizeof cwd)) std::strcpy(cwd, ".");
+    char *abs = realpath(cwd, nullptr);
+    std::string src = abs ? abs : cwd;
+    if (abs) free(abs);
+    return md5_hex(src);
+  }();
+  return cached_id;
 }
 
 /* ----------------------------- MD5 ------------------------------------ */
@@ -322,7 +355,11 @@ bool read_file_str(std::string_view path, std::string &out) {
   std::string p(path);
   FILE *f = std::fopen(p.c_str(), "rb");
   if (!f) return false;
-  char buf[4096];
+  struct stat st;
+  if (fstat(fileno(f), &st) == 0 && S_ISREG(st.st_mode) && st.st_size > 0) {
+    out.reserve((size_t)st.st_size);
+  }
+  char buf[16384];
   size_t n;
   while ((n = std::fread(buf, 1, sizeof buf, f)) > 0) {
     out.append(buf, n);