[libc-commits] [libc] fe99de3 - [libc] Enable spawn lib in riscv

[Mikhail R. Gadelha via libc-commits]

Author: Mikhail R. Gadelha
Date: 2023-03-16T06:16:14-03:00
New Revision: fe99de31d949187fa9759de581041bb1aff460ea

URL: https://github.com/llvm/llvm-project/commit/fe99de31d949187fa9759de581041bb1aff460ea
DIFF: https://github.com/llvm/llvm-project/commit/fe99de31d949187fa9759de581041bb1aff460ea.diff

LOG: [libc] Enable spawn lib in riscv

In this patch we add support for the spawn lib in riscv.

Only small changes were required, the biggest one was to use of dup3
instead of dup2, if the latter is not available. This follows our
implementation of dup2.

Differential Revision: https://reviews.llvm.org/D146145

Added: 
    

Modified: 
    libc/config/linux/riscv64/entrypoints.txt
    libc/config/linux/riscv64/headers.txt
    libc/src/spawn/linux/posix_spawn.cpp

Removed: 
    


################################################################################
diff  --git a/libc/config/linux/riscv64/entrypoints.txt b/libc/config/linux/riscv64/entrypoints.txt
index 2d0df5cde2671..042671fa1833a 100644
--- a/libc/config/linux/riscv64/entrypoints.txt
+++ b/libc/config/linux/riscv64/entrypoints.txt
@@ -431,6 +431,14 @@ if(LLVM_LIBC_FULL_BUILD)
     libc.src.signal.sigfillset
     libc.src.signal.signal
 
+    # spawn.h entrypoints
+    libc.src.spawn.posix_spawn
+    libc.src.spawn.posix_spawn_file_actions_addclose
+    libc.src.spawn.posix_spawn_file_actions_adddup2
+    libc.src.spawn.posix_spawn_file_actions_addopen
+    libc.src.spawn.posix_spawn_file_actions_destroy
+    libc.src.spawn.posix_spawn_file_actions_init
+
     # threads.h entrypoints
     libc.src.threads.call_once
     libc.src.threads.cnd_broadcast

diff  --git a/libc/config/linux/riscv64/headers.txt b/libc/config/linux/riscv64/headers.txt
index 1b6dea68e238a..6d7e53790ec12 100644
--- a/libc/config/linux/riscv64/headers.txt
+++ b/libc/config/linux/riscv64/headers.txt
@@ -9,6 +9,7 @@ set(TARGET_PUBLIC_HEADERS
     libc.include.pthread
     libc.include.sched
     libc.include.signal
+    libc.include.spawn
     libc.include.stdio
     libc.include.stdlib
     libc.include.string

diff  --git a/libc/src/spawn/linux/posix_spawn.cpp b/libc/src/spawn/linux/posix_spawn.cpp
index 2f8287238ec86..504ac5d0a3938 100644
--- a/libc/src/spawn/linux/posix_spawn.cpp
+++ b/libc/src/spawn/linux/posix_spawn.cpp
@@ -14,6 +14,7 @@
 #include "src/spawn/file_actions.h"
 
 #include <fcntl.h>
+#include <signal.h> // For SIGCHLD
 #include <spawn.h>
 #include <sys/syscall.h> // For syscall numbers.
 
@@ -50,8 +51,15 @@ cpp::optional<int> open(const char *path, int oflags, mode_t mode) {
 
 void close(int fd) { __llvm_libc::syscall_impl(SYS_close, fd); }
 
+// We use dup3 if dup2 is not available, similar to our implementation of dup2
 bool dup2(int fd, int newfd) {
+#ifdef SYS_dup2
   long ret = __llvm_libc::syscall_impl(SYS_dup2, fd, newfd);
+#elif defined(SYS_dup3)
+  long ret = __llvm_libc::syscall_impl(SYS_dup3, fd, newfd, 0);
+#else
+#error "SYS_dup2 and SYS_dup3 not available for the target."
+#endif
   return ret < 0 ? false : true;
 }