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

tools.cpp

@@ -1,5 +1,6 @@
 /* tools.cpp — bash/read/write tools and oversized result offloading. */
 #include "bantam.hpp"
+#include <algorithm>
 #include <array>
 #include <cerrno>
 #include <cstdio>
@@ -20,6 +21,8 @@
  * be located anywhere on PATH. Never returns a hardcoded bash path. */
 static const char *resolve_shell() {
   static char buf[4096];
+  static const char *cached = nullptr;
+  if (cached) return cached;
   const char *path = getenv("PATH");
   if (path && *path) {
     std::string p(path);
@@ -34,19 +37,22 @@ static const char *resolve_shell() {
       if (stat(cand.c_str(), &st) == 0 && S_ISREG(st.st_mode) &&
           (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0) {
         snprintf(buf, sizeof buf, "%s", cand.c_str());
-        return buf;
+        cached = buf;
+        return cached;
       }
       if (end == std::string::npos) break;
       start = end + 1;
     }
   }
-  return "/bin/sh";
+  cached = "/bin/sh";
+  return cached;
 }
 
 std::string shell_with_workdir(std::string_view cmd, std::string_view workdir,
                                int timeout, volatile int *interrupted) {
   std::string fcmd = filter_text(cmd);
   if (timeout <= 0) timeout = 120;
+  const char *sh = resolve_shell();
 
   int pipefd[2];
   if (pipe(pipefd) != 0) return "[tool error: pipe failed]";
@@ -57,13 +63,14 @@ std::string shell_with_workdir(std::string_view cmd, std::string_view workdir,
     return "[tool error: fork failed]";
   }
   if (pid == 0) {
-    /* child */
+    /* child: create a dedicated process group so timeout/SIGINT kills the
+     * entire process tree spawned by the shell. */
+    setpgid(0, 0);
     dup2(pipefd[1], STDOUT_FILENO);
     dup2(pipefd[1], STDERR_FILENO);
     close(pipefd[0]);
     close(pipefd[1]);
     if (!workdir.empty()) chdir(std::string(workdir).c_str());
-    const char *sh = resolve_shell();
     const char *shname = (strrchr(sh, '/') ? strrchr(sh, '/') + 1 : sh);
     execl(sh, shname, "-c", fcmd.c_str(), (char *)nullptr);
     _exit(127);
@@ -81,9 +88,11 @@ std::string shell_with_workdir(std::string_view cmd, std::string_view workdir,
     if (*interrupted) break;
     int remain = (int)(deadline - time(nullptr));
     if (remain <= 0) { killed = true; break; }
-    int pr = poll(&pfd, 1, remain * 1000);
+    int wait_ms = remain * 1000;
+    if (wait_ms > 200) wait_ms = 200;
+    int pr = poll(&pfd, 1, wait_ms);
     if (pr < 0) { if (errno == EINTR) continue; break; }
-    if (pr == 0) { killed = true; break; }
+    if (pr == 0) continue;
     char buf[4096];
     ssize_t n = read(pipefd[0], buf, sizeof buf);
     if (n > 0) out.append(buf, (size_t)n);
@@ -92,6 +101,7 @@ std::string shell_with_workdir(std::string_view cmd, std::string_view workdir,
     else break;
   }
   if (*interrupted || killed) {
+    kill(-pid, SIGKILL);
     kill(pid, SIGKILL);
     /* drain remaining output briefly */
     struct pollfd dpfd; dpfd.fd = pipefd[0]; dpfd.events = POLLIN;
@@ -141,29 +151,41 @@ std::string read_file_or_dir(std::string_view path, int offset, int limit, int *
     return sfmt("[tool error: read %s: %s]", p.c_str(), strerror(errno));
   }
   if (S_ISDIR(st.st_mode)) {
-    std::vector<std::string> raw_names;
+    struct DirEnt {
+      std::string name;
+      int is_dir; /* -1 = unknown, 0 = non-dir, 1 = dir */
+    };
+    std::vector<DirEnt> entries;
     {
       DIR *dir = opendir(p.c_str());
       if (!dir) { *style = 31; return "[tool error: read (directory listing failed)]"; }
       struct dirent *de;
       while ((de = readdir(dir))) {
-        std::string nm = de->d_name;
-        if (nm == "." || nm == "..") continue;
-        raw_names.push_back(std::move(nm));
+        if (de->d_name[0] == '.' &&
+            (de->d_name[1] == '\0' || (de->d_name[1] == '.' && de->d_name[2] == '\0')))
+          continue;
+        int isdir = -1;
+#if defined(DT_DIR) && defined(DT_UNKNOWN) && defined(DT_LNK)
+        if (de->d_type != DT_UNKNOWN && de->d_type != DT_LNK) {
+          isdir = (de->d_type == DT_DIR) ? 1 : 0;
+        }
+#endif
+        entries.push_back(DirEnt{de->d_name, isdir});
       }
       closedir(dir);
     }
-    for (size_t i = 1; i < raw_names.size(); i++) {
-      for (size_t j = i; j > 0 && raw_names[j - 1] > raw_names[j]; j--) {
-        std::swap(raw_names[j - 1], raw_names[j]);
-      }
-    }
+    std::sort(entries.begin(), entries.end(), [](const DirEnt &a, const DirEnt &b) {
+      return a.name < b.name;
+    });
     std::string b;
-    for (auto &nm : raw_names) {
-      std::string full = p + "/" + nm;
-      struct stat ds;
-      bool isdir = (stat(full.c_str(), &ds) == 0 && S_ISDIR(ds.st_mode));
-      b += nm;
+    for (auto &ent : entries) {
+      bool isdir = (ent.is_dir == 1);
+      if (ent.is_dir < 0) {
+        std::string full = p + "/" + ent.name;
+        struct stat ds;
+        isdir = (stat(full.c_str(), &ds) == 0 && S_ISDIR(ds.st_mode));
+      }
+      b += ent.name;
       if (isdir) b += '/';
       b += '\n';
     }