From de6041fedef397a1843706ee7af43f9ef8ad7b71 Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Wed, 12 Oct 2022 20:19:13 +0200
Subject: [PATCH] libc: Add fdopen()

---
 libs/libc/include/stdio.h |  3 +++
 libs/libc/src/file.cpp    | 13 +++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/libs/libc/include/stdio.h b/libs/libc/include/stdio.h
index 0173caac..b0e0aab9 100644
--- a/libs/libc/include/stdio.h
+++ b/libs/libc/include/stdio.h
@@ -32,6 +32,9 @@ extern "C"
     /* Opens the file specified by pathname. Returns the file handle on success, or NULL on error. */
     FILE* fopen(const char* pathname, const char* mode);
 
+    /* Returns a new file associated with the file descriptor fd. */
+    FILE* fdopen(int fd, const char* mode);
+
     /* Writes formatted output according to the string format to the file stream. */
     int fprintf(FILE* stream, const char* format, ...);
 
diff --git a/libs/libc/src/file.cpp b/libs/libc/src/file.cpp
index 2aade1dd..e0525a22 100644
--- a/libs/libc/src/file.cpp
+++ b/libs/libc/src/file.cpp
@@ -40,6 +40,19 @@ extern "C"
         return stream;
     }
 
+    FILE* fdopen(int fd, const char*)
+    {
+        if (fd < 0) // FIXME: Also check if the mode string is compatible with how fd was opened.
+        {
+            errno = EBADF;
+            return 0;
+        }
+        FILE* stream = (FILE*)malloc(sizeof(FILE));
+        stream->f_fd = fd;
+        clearerr(stream);
+        return stream;
+    }
+
     size_t fread(void* buf, size_t size, size_t nmemb, FILE* stream)
     {
         ssize_t status = read(stream->f_fd, buf, size * nmemb);