From 5f018c18b4d7643b3cf0ba0f47648507666588a3 Mon Sep 17 00:00:00 2001
From: Francesco Cozzuto <francesco.cozzuto@gmail.com>
Date: Sun, 9 Nov 2025 16:49:15 +0100
Subject: [PATCH] Progress

---
 src/chunk_server.c | 23 ++++++++++++-
 src/file_system.c  | 81 ----------------------------------------------
 src/system.c       | 25 +++++++++++---
 src/system.h       |  1 +
 4 files changed, 44 insertions(+), 86 deletions(-)

diff --git a/src/chunk_server.c b/src/chunk_server.c
index 6df5f02..2a880a0 100644
--- a/src/chunk_server.c
+++ b/src/chunk_server.c
@@ -90,6 +90,7 @@ static int load_chunk(ChunkStore *store, SHA256 hash, string *data)
 {
     char buf[PATH_MAX];
     string path = hash2path(store, hash, buf);
+    // TODO: check that the hash matches
     return file_read_all(path, data);
 }
 
@@ -98,7 +99,27 @@ static int store_chunk(ChunkStore *store, string data, SHA256 *hash)
     sha256(data.ptr, data.len, (uint8_t*) hash->data);
     char buf[PATH_MAX];
     string path = hash2path(store, *hash, buf);
-    return file_write_atomic(path, data);
+
+    // Note that this write is not atomic. If we crash
+    // while writing, we'll get an inconsistent file.
+    // This is okay as long as we check that the hash
+    // is correct while reading back the data.
+    Handle fd;
+    if (file_open(path, &fd) < 0)
+        return -1;
+    int copied = 0;
+    while (copied < data.len) {
+        int ret = file_write(fd,
+            data.ptr + copied,
+            data.len - copied);
+        if (ret < 0) {
+            file_close(fd);
+            return -1;
+        }
+        copied += ret;
+    }
+    file_close(fd);
+    return 0;
 }
 
 static int chunk_store_get(ChunkStore *store, SHA256 hash, string *data)
diff --git a/src/file_system.c b/src/file_system.c
index 6d04ee5..c64f630 100644
--- a/src/file_system.c
+++ b/src/file_system.c
@@ -157,87 +157,6 @@ int file_size(Handle fd, size_t *len)
 #endif
 }
 
-// TODO: port to windows
-#ifndef _WIN32
-// TODO: test this
-static string parent_path(string path)
-{
-    if (path.len > 0 && path.ptr[path.len-1] == '/')
-        path.len--;
-
-    if (path.len == 0)
-        return S("");
-
-    while (path.len > 0 && path.ptr[path.len-1] != '/')
-        path.len--;
-
-    if (path.len > 0)
-        path.len--;
-
-    return path;
-}
-static int write_bytes(int fd, string data)
-{
-    size_t written = 0;
-    while (written < (size_t) data.len) {
-        int ret = sys_write(fd, data.ptr + written, data.len - written);
-        if (ret < 0) {
-            if (errno == EINTR)
-                continue;
-            return -1;
-        }
-        written += (size_t) ret;
-    }
-    assert((size_t) data.len == written);
-    return 0;
-}
-int file_write_atomic(string path, string content)
-{
-    string parent = parent_path(path);
-
-    char pattern[] = "/tmp_XXXXXXXX";
-
-    char tmp_path[PATH_MAX];
-    if (parent.len + strlen(pattern) >= (int) sizeof(tmp_path))
-        return -1;
-    memcpy(tmp_path, parent.ptr, parent.len);
-    memcpy(tmp_path + parent.len, pattern, strlen(pattern));
-    tmp_path[parent.len + strlen(pattern)] = '\0';
-
-    int fd = sys_mkstemp(tmp_path);
-    if (fd < 0)
-        return -1;
-
-    if (write_bytes(fd, content) < 0) {
-        sys_close(fd);
-        sys_remove(tmp_path);
-        return -1;
-    }
-
-#ifdef _WIN32
-    if (sys__commit(fd)) {
-        sys_close(fd);
-        sys_remove(tmp_path);
-        return -1;
-    }
-#else
-    if (sys_fsync(fd)) {
-        sys_close(fd);
-        sys_remove(tmp_path);
-        return -1;
-    }
-#endif
-
-    close(fd);
-
-    if (rename_file_or_dir((string) { tmp_path, strlen(tmp_path) }, path)) {
-        sys_remove(tmp_path);
-        return -1;
-    }
-    return 0;
-}
-#endif
-
 int create_dir(string path)
 {
     char zt[PATH_MAX];
diff --git a/src/system.c b/src/system.c
index 73adcfc..52e6e6e 100644
--- a/src/system.c
+++ b/src/system.c
@@ -1174,7 +1174,7 @@ int mock_connect(SOCKET fd, void *addr, size_t addr_len)
     return -1;
 }
 
-static NATIVE_HANDLE
+static int
 wrap_native_file_into_desc(NATIVE_HANDLE handle)
 {
     if (current_process->num_desc == MAX_DESCRIPTORS) {
@@ -1290,7 +1290,12 @@ HANDLE mock_CreateFileW(WCHAR *lpFileName, DWORD dwDesiredAccess,
         dwFlagsAndAttributes, hTemplateFile);
     if (handle == INVALID_HANDLE_VALUE)
         return INVALID_HANDLE_VALUE;
-    return wrap_native_file_into_desc(handle);
+    int fd = wrap_native_file_into_desc(handle);
+    if (fd < 0) {
+        CloseHandle(handle);
+        return INVALID_HANDLE_VALUE;
+    }
+    return (HANDLE) fd;
 }
 
 BOOL mock_CloseHandle(HANDLE handle)
@@ -1506,7 +1511,13 @@ int mock_open(char *path, int flags, int mode)
     int fd = open(path, flags, mode);
     if (fd < 0) return -1;
 
-    return wrap_native_file_into_desc(fd);
+    int wrapped_fd = wrap_native_file_into_desc(fd);
+    if (wrapped_fd < 0) {
+        close(fd);
+        return -1;
+    }
+
+    return wrapped_fd;
 }
 
 int mock_close(int fd)
@@ -1634,7 +1645,13 @@ int mock_mkstemp(char *path)
     int fd = mkstemp(path);
     if (fd < 0) return fd;
 
-    return wrap_native_file_into_desc(fd);
+    int wrapped_fd = wrap_native_file_into_desc(fd);
+    if (wrapped_fd < 0) {
+        close(fd);
+        return -1;
+    }
+
+    return wrapped_fd;
 }
 
 char* mock_realpath(char *path, char *dst)
diff --git a/src/system.h b/src/system.h
index b532c92..c2bc896 100644
--- a/src/system.h
+++ b/src/system.h
@@ -2,6 +2,7 @@
 #define SYSTEM_INCLUDED
 
 #include <stdio.h>
+#include <stdint.h>
 #include <stdlib.h>
 
 #ifdef _WIN32