From 40404f0479ae284cedd1816630d9eab28f33c69b Mon Sep 17 00:00:00 2001
From: Filipp Zhinkin <filipp.zhinkin@jetbrains.com>
Date: Wed, 18 Dec 2024 18:33:10 -0500
Subject: [PATCH] Check error codes returned by POSIX-ish APIs and throw IOE

---
 .../src/files/FileSystemAndroid.kt             | 11 +++++++++--
 core/native/src/files/PathsNative.kt           | 18 +++++++++++++-----
 .../src/files/FileSystemNativeNonAndroid.kt    | 11 +++++++++--
 core/wasmWasi/src/files/FileSystemWasm.kt      | 15 ++++++++++++---
 4 files changed, 43 insertions(+), 12 deletions(-)

diff --git a/core/androidNative/src/files/FileSystemAndroid.kt b/core/androidNative/src/files/FileSystemAndroid.kt
index 65ba74177..24fbba52e 100644
--- a/core/androidNative/src/files/FileSystemAndroid.kt
+++ b/core/androidNative/src/files/FileSystemAndroid.kt
@@ -35,7 +35,11 @@ internal actual class OpaqueDirEntry(private val dir: CPointer<cnames.structs.DI
     }
 
     actual override fun close() {
-        closedir(dir)
+        if (closedir(dir) != 0) {
+            val err = errno
+            val strerr = strerror(err)?.toKString() ?: "unknown error"
+            throw IOException("closedir failed with errno $err ($strerr)")
+        }
     }
 }
 
@@ -43,5 +47,8 @@ internal actual class OpaqueDirEntry(private val dir: CPointer<cnames.structs.DI
 internal actual fun opendir(path: String): OpaqueDirEntry {
     val dirent = platform.posix.opendir(path)
     if (dirent != null) return OpaqueDirEntry(dirent)
-    throw IOException("Can't open directory $path: ${strerror(errno)?.toKString() ?: "reason unknown"}")
+
+    val err = errno
+    val strerr = strerror(err)?.toKString() ?: "unknown error"
+    throw IOException("Can't open directory $path: $err ($strerr)")
 }
diff --git a/core/native/src/files/PathsNative.kt b/core/native/src/files/PathsNative.kt
index 9e2f4a2a7..e013afd60 100644
--- a/core/native/src/files/PathsNative.kt
+++ b/core/native/src/files/PathsNative.kt
@@ -64,6 +64,12 @@ internal expect fun isAbsoluteImpl(path: String): Boolean
 
 public actual fun Path(path: String): Path = Path(path, null)
 
+private fun throwIOExceptionForErrno(operation: String): Nothing {
+    val err = errno
+    val strerr = strerror(err)?.toKString() ?: "unknown error"
+    throw IOException("$operation failed with errno $err ($strerr)")
+}
+
 internal class FileSource(
     private val file: CPointer<FILE>
 ) : RawSource {
@@ -85,7 +91,7 @@ internal class FileSource(
         return when {
             bytesRead == byteCount -> bytesRead
             feof(file) != 0 -> if (bytesRead == 0L) -1L else bytesRead
-            ferror(file) != 0 -> throw IOException(errno.toString())
+            ferror(file) != 0 -> throwIOExceptionForErrno("write")
             else -> bytesRead
         }
     }
@@ -93,7 +99,9 @@ internal class FileSource(
     override fun close() {
         if (closed) return
         closed = true
-        fclose(file)
+        if (fclose(file) != 0) {
+            throwIOExceptionForErrno("fclose")
+        }
     }
 }
 
@@ -130,13 +138,13 @@ internal class FileSink(
             variantFwrite(pinned.addressOf(0), byteCount.toUInt(), file).toLong()
         }
         if (bytesWritten < byteCount) {
-            throw IOException(errno.toString())
+            throwIOExceptionForErrno("file write")
         }
     }
 
     override fun flush() {
         if (fflush(file) != 0) {
-            throw IOException(errno.toString())
+            throwIOExceptionForErrno("fflush")
         }
     }
 
@@ -144,7 +152,7 @@ internal class FileSink(
         if (closed) return
         closed = true
         if (fclose(file) != 0) {
-            throw IOException(errno.toString())
+            throwIOExceptionForErrno("fclose")
         }
     }
 }
diff --git a/core/nativeNonAndroid/src/files/FileSystemNativeNonAndroid.kt b/core/nativeNonAndroid/src/files/FileSystemNativeNonAndroid.kt
index f36286345..a75172231 100644
--- a/core/nativeNonAndroid/src/files/FileSystemNativeNonAndroid.kt
+++ b/core/nativeNonAndroid/src/files/FileSystemNativeNonAndroid.kt
@@ -23,7 +23,11 @@ internal actual class OpaqueDirEntry(private val dir: CPointer<DIR>) : AutoClose
     }
 
     actual override fun close() {
-        closedir(dir)
+        if (closedir(dir) != 0) {
+            val err = errno
+            val strerr = strerror(err)?.toKString() ?: "unknown error"
+            throw IOException("closedir failed with errno $err ($strerr)")
+        }
     }
 }
 
@@ -31,5 +35,8 @@ internal actual class OpaqueDirEntry(private val dir: CPointer<DIR>) : AutoClose
 internal actual fun opendir(path: String): OpaqueDirEntry {
     val dirent = platform.posix.opendir(path)
     if (dirent != null) return OpaqueDirEntry(dirent)
-    throw IOException("Can't open directory $path: ${strerror(errno)?.toKString() ?: "reason unknown"}")
+
+    val err = errno
+    val strerr = strerror(err)?.toKString() ?: "unknown error"
+    throw IOException("Can't open directory $path: $err ($strerr)")
 }
diff --git a/core/wasmWasi/src/files/FileSystemWasm.kt b/core/wasmWasi/src/files/FileSystemWasm.kt
index 19810c8b1..252fbe30b 100644
--- a/core/wasmWasi/src/files/FileSystemWasm.kt
+++ b/core/wasmWasi/src/files/FileSystemWasm.kt
@@ -344,7 +344,10 @@ internal object WasiFileSystem : SystemFileSystemImpl() {
             }
             return children
         } finally {
-            fd_close(dir_fd)
+            val res = Errno(fd_close(dir_fd))
+            if (res != Errno.success) {
+                throw IOException("fd_close failed for directory '$directory': ${res.description}")
+            }
         }
     }
 }
@@ -488,7 +491,10 @@ private class FileSink(private val fd: Fd) : RawSink {
     override fun close() {
         if (!closed) {
             closed = true
-            fd_close(fd)
+            val res = Errno(fd_close(fd))
+            if (res != Errno.success) {
+                throw IOException("fd_close failed: ${res.description}")
+            }
         }
     }
 }
@@ -536,7 +542,10 @@ private class FileSource(private val fd: Fd) : RawSource {
     override fun close() {
         if (!closed) {
             closed = true
-            fd_close(fd)
+            val res = Errno(fd_close(fd))
+            if (res != Errno.success) {
+                throw IOException("fd_close failed: ${res.description}")
+            }
         }
     }
 }