From 2abb43d70964cc09f822960c21ca07a597bb1a88 Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Tue, 22 Aug 2023 11:54:00 +0200
Subject: [PATCH] kernel+libos: Call Vector::try_reserve where it is
 appropriate

---
 kernel/src/binfmt/Script.cpp      | 1 +
 kernel/src/sys/poll.cpp           | 4 +++-
 kernel/src/thread/ThreadImage.cpp | 1 +
 libos/src/Process.cpp             | 8 ++++++++
 4 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/kernel/src/binfmt/Script.cpp b/kernel/src/binfmt/Script.cpp
index 6af3f612..f9c5f3d8 100644
--- a/kernel/src/binfmt/Script.cpp
+++ b/kernel/src/binfmt/Script.cpp
@@ -49,6 +49,7 @@ Result<u64> ScriptLoader::load(AddressSpace* space)
 Result<Vector<String>> ScriptLoader::cmdline(const String& path, Vector<String> args)
 {
     Vector<String> new_args;
+    TRY(new_args.try_reserve(m_interpreter_cmdline.size() + args.size() + 1));
     for (auto& arg : m_interpreter_cmdline) { TRY(new_args.try_append(move(arg))); }
     auto arg = TRY(path.clone());
     TRY(new_args.try_append(move(arg)));
diff --git a/kernel/src/sys/poll.cpp b/kernel/src/sys/poll.cpp
index 3283098f..cfdc4247 100644
--- a/kernel/src/sys/poll.cpp
+++ b/kernel/src/sys/poll.cpp
@@ -17,10 +17,12 @@ Result<u64> sys_poll(Registers*, SyscallArgs args)
 
     if (!MemoryManager::copy_from_user(fds, kfds, nfds * sizeof(pollfd))) return err(EFAULT);
 
-    Vector<SharedPtr<VFS::Inode>> inodes;
     auto* current = Scheduler::current();
     TRY(check_pledge(current, Promise::p_stdio));
 
+    Vector<SharedPtr<VFS::Inode>> inodes;
+    TRY(inodes.try_reserve(nfds));
+
     for (nfds_t i = 0; i < nfds; i++)
     {
         int fd = kfds[i].fd;
diff --git a/kernel/src/thread/ThreadImage.cpp b/kernel/src/thread/ThreadImage.cpp
index 9b79e0c1..3d03fd0c 100644
--- a/kernel/src/thread/ThreadImage.cpp
+++ b/kernel/src/thread/ThreadImage.cpp
@@ -88,6 +88,7 @@ Result<u64> ThreadImage::push_mem_on_stack(const u8* mem, usize size)
 Result<u64> ThreadImage::push_string_vector_on_stack(const Vector<String>& vec)
 {
     Vector<u64> user_vec;
+    TRY(user_vec.try_reserve(vec.size() + 1));
     for (const auto& item : vec)
     {
         // Copy each individual string and retrieve a userspace pointer to said copy
diff --git a/libos/src/Process.cpp b/libos/src/Process.cpp
index 81a40ee2..b533908d 100644
--- a/libos/src/Process.cpp
+++ b/libos/src/Process.cpp
@@ -26,6 +26,7 @@ namespace os
     Result<void> Process::exec(StringView path, Slice<String> args, bool search_in_path)
     {
         Vector<const char*> argv;
+        TRY(argv.try_reserve(args.size() + 1));
         for (const auto& arg : args) { TRY(argv.try_append(arg.chars())); }
         TRY(argv.try_append(nullptr));
 
@@ -39,6 +40,7 @@ namespace os
     Result<void> Process::exec(StringView path, Slice<StringView> args, bool search_in_path)
     {
         Vector<const char*> argv;
+        TRY(argv.try_reserve(args.size() + 1));
         for (const auto& arg : args) { TRY(argv.try_append(arg.chars())); }
         TRY(argv.try_append(nullptr));
 
@@ -52,10 +54,12 @@ namespace os
     Result<void> Process::exec(StringView path, Slice<String> args, Slice<String> env, bool search_in_path)
     {
         Vector<const char*> argv;
+        TRY(argv.try_reserve(args.size() + 1));
         for (const auto& arg : args) { TRY(argv.try_append(arg.chars())); }
         TRY(argv.try_append(nullptr));
 
         Vector<const char*> envp;
+        TRY(envp.try_reserve(env.size() + 1));
         for (const auto& arg : env) { TRY(envp.try_append(arg.chars())); }
         TRY(envp.try_append(nullptr));
 
@@ -83,6 +87,7 @@ namespace os
     Result<pid_t> Process::spawn(StringView path, Slice<String> args, bool search_in_path)
     {
         Vector<const char*> argv;
+        TRY(argv.try_reserve(args.size() + 1));
         for (const auto& arg : args) { TRY(argv.try_append(arg.chars())); }
         TRY(argv.try_append(nullptr));
 
@@ -92,6 +97,7 @@ namespace os
     Result<pid_t> Process::spawn(StringView path, Slice<StringView> args, bool search_in_path)
     {
         Vector<const char*> argv;
+        TRY(argv.try_reserve(args.size() + 1));
         for (const auto& arg : args) { TRY(argv.try_append(arg.chars())); }
         TRY(argv.try_append(nullptr));
 
@@ -101,10 +107,12 @@ namespace os
     Result<pid_t> Process::spawn(StringView path, Slice<String> args, Slice<String> env, bool search_in_path)
     {
         Vector<const char*> argv;
+        TRY(argv.try_reserve(args.size() + 1));
         for (const auto& arg : args) { TRY(argv.try_append(arg.chars())); }
         TRY(argv.try_append(nullptr));
 
         Vector<const char*> envp;
+        TRY(envp.try_reserve(env.size() + 1));
         for (const auto& arg : env) { TRY(envp.try_append(arg.chars())); }
         TRY(envp.try_append(nullptr));