Add filesystem API

2 files changed, 345 insertions, 0 deletions

diff --git a/src/win32/filesystem_win32.c b/src/win32/filesystem_win32.c
new file mode 100644
index 0000000..3e9b7a6
--- /dev/null
+++ b/src/win32/filesystem_win32.c
@@ -0,0 +1,325 @@
+// Copyright 2007-2022 David Robillard <d@drobilla.net>
+// SPDX-License-Identifier: ISC
+
+#define _WIN32_WINNT 0x0600 // Vista
+
+#include "zix/bump_allocator.h"
+#include "zix/filesystem.h"
+
+#include "../errno_status.h"
+#include "../zix_config.h"
+
+#include "zix/allocator.h"
+#include "zix/path.h"
+#include "zix/status.h"
+
+#include <direct.h>
+#include <fcntl.h>
+#include <io.h>
+#include <limits.h>
+#include <sys/stat.h>
+#include <windows.h>
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static inline ZixStatus
+zix_winerror_status(const DWORD e)
+{
+  switch (e) {
+  case ERROR_NOT_ENOUGH_MEMORY:
+  case ERROR_OUTOFMEMORY:
+    return ZIX_STATUS_NO_MEM;
+  case ERROR_SEM_TIMEOUT:
+    return ZIX_STATUS_TIMEOUT;
+  case ERROR_FILE_NOT_FOUND:
+  case ERROR_PATH_NOT_FOUND:
+    return ZIX_STATUS_NOT_FOUND;
+  case ERROR_BUFFER_OVERFLOW:
+    return ZIX_STATUS_OVERFLOW;
+  case ERROR_DISK_FULL:
+    return ZIX_STATUS_NO_SPACE;
+  case ERROR_ALREADY_EXISTS:
+  case ERROR_FILE_EXISTS:
+    return ZIX_STATUS_EXISTS;
+  case ERROR_PRIVILEGE_NOT_HELD:
+    return ZIX_STATUS_BAD_PERMS;
+  case ERROR_LOCK_VIOLATION:
+    return ZIX_STATUS_UNAVAILABLE;
+  }
+
+  return ZIX_STATUS_ERROR;
+}
+
+static inline ZixStatus
+zix_windows_status(const bool success)
+{
+  return success ? ZIX_STATUS_SUCCESS : zix_winerror_status(GetLastError());
+}
+
+ZixStatus
+zix_copy_file(ZixAllocator* const  allocator,
+              const char* const    src,
+              const char* const    dst,
+              const ZixCopyOptions options)
+{
+  (void)allocator;
+
+  return zix_windows_status(
+    CopyFile(src, dst, !(options & ZIX_COPY_OPTION_OVERWRITE_EXISTING)));
+}
+
+char*
+zix_create_temporary_directory(ZixAllocator* const allocator,
+                               const char* const   path_pattern)
+{
+  static const char chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+  static const int  n_chars = sizeof(chars) - 1;
+
+  // Ensure that the pattern ends with "XXXXXX"
+  const size_t length = strlen(path_pattern);
+  if (length < 7 || strcmp(path_pattern + length - 6, "XXXXXX")) {
+    errno = EINVAL;
+    return NULL;
+  }
+
+  // Allocate a result to manipulate as we search for paths
+  char* const result = (char*)zix_calloc(allocator, length + 1U, 1U);
+  if (!result) {
+    return NULL;
+  }
+
+  // Repeatedly try creating a directory with random suffixes
+  memcpy(result, path_pattern, length + 1U);
+  char* const suffix = result + length - 6U;
+  for (unsigned attempt = 0U; attempt < 128U; ++attempt) {
+    for (unsigned i = 0U; i < 6U; ++i) {
+      suffix[i] = chars[rand() % n_chars];
+    }
+
+    if (!_mkdir(result)) {
+      return result;
+    }
+  }
+
+  zix_free(allocator, result);
+  return NULL;
+}
+
+ZixStatus
+zix_remove(const char* const path)
+{
+  return ((zix_file_type(path) == ZIX_FILE_TYPE_DIRECTORY)
+            ? zix_windows_status(RemoveDirectory(path))
+          : remove(path) ? zix_errno_status(errno)
+                         : ZIX_STATUS_SUCCESS);
+}
+
+void
+zix_dir_for_each(const char* const path,
+                 void* const       data,
+                 void (*const f)(const char* path,
+                                 const char* name,
+                                 void*       data))
+{
+  const size_t path_len = strlen(path);
+  char         pat[MAX_PATH + 2U];
+  memcpy(pat, path, path_len + 1U);
+  pat[path_len]      = '\\';
+  pat[path_len + 1U] = '*';
+  pat[path_len + 2U] = '\0';
+
+  WIN32_FIND_DATA fd;
+  HANDLE          fh = FindFirstFile(pat, &fd);
+  if (fh != INVALID_HANDLE_VALUE) {
+    do {
+      if (!!strcmp(fd.cFileName, ".") && !!strcmp(fd.cFileName, "..")) {
+        f(path, fd.cFileName, data);
+      }
+    } while (FindNextFile(fh, &fd));
+  }
+  FindClose(fh);
+}
+
+ZixStatus
+zix_file_lock(FILE* const file, const ZixFileLockMode mode)
+{
+  HANDLE     handle     = (HANDLE)_get_osfhandle(fileno(file));
+  OVERLAPPED overlapped = {0};
+
+  const DWORD flags =
+    (LOCKFILE_EXCLUSIVE_LOCK |
+     (mode == ZIX_FILE_LOCK_TRY ? LOCKFILE_FAIL_IMMEDIATELY : 0));
+
+  return zix_windows_status(
+    LockFileEx(handle, flags, 0, UINT32_MAX, UINT32_MAX, &overlapped));
+}
+
+ZixStatus
+zix_file_unlock(FILE* const file, const ZixFileLockMode mode)
+{
+  (void)mode;
+
+  HANDLE     handle     = (HANDLE)_get_osfhandle(fileno(file));
+  OVERLAPPED overlapped = {0};
+
+  return zix_windows_status(
+    UnlockFileEx(handle, 0, UINT32_MAX, UINT32_MAX, &overlapped));
+}
+
+char*
+zix_canonical_path(ZixAllocator* const allocator, const char* const path)
+{
+  char full[MAX_PATH] = {0};
+  if (!path || !GetFullPathName(path, MAX_PATH, full, NULL)) {
+    return NULL;
+  }
+
+  const HANDLE h =
+    CreateFile(full,
+               FILE_READ_ATTRIBUTES,
+               FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+               NULL,
+               OPEN_EXISTING,
+               FILE_FLAG_BACKUP_SEMANTICS,
+               NULL);
+
+  const DWORD flags      = FILE_NAME_NORMALIZED | VOLUME_NAME_DOS;
+  const DWORD final_size = GetFinalPathNameByHandle(h, NULL, 0U, flags);
+  if (!final_size) {
+    CloseHandle(h);
+    return NULL;
+  }
+
+  char* const final = (char*)zix_calloc(allocator, final_size + 1U, 1U);
+  if (final && !GetFinalPathNameByHandle(h, final, final_size + 1U, flags)) {
+    zix_free(allocator, final);
+    CloseHandle(h);
+    return NULL;
+  }
+
+  CloseHandle(h);
+  return final;
+}
+
+static ZixFileType
+attrs_file_type(const DWORD attrs)
+{
+  if (attrs == INVALID_FILE_ATTRIBUTES) {
+    return ZIX_FILE_TYPE_NONE;
+  }
+
+  if (attrs & FILE_ATTRIBUTE_DIRECTORY) {
+    return ZIX_FILE_TYPE_DIRECTORY;
+  }
+
+  if (attrs & FILE_ATTRIBUTE_REPARSE_POINT) {
+    return ZIX_FILE_TYPE_SYMLINK;
+  }
+
+  if (attrs & (FILE_ATTRIBUTE_DEVICE)) {
+    return ZIX_FILE_TYPE_UNKNOWN;
+  }
+
+  return ZIX_FILE_TYPE_REGULAR;
+}
+
+ZixFileType
+zix_file_type(const char* const path)
+{
+  const ZixFileType type = attrs_file_type(GetFileAttributes(path));
+  if (type != ZIX_FILE_TYPE_SYMLINK) {
+    return type;
+  }
+
+  // Resolve symlink to find the canonical type
+  char             buf[MAX_PATH];
+  ZixBumpAllocator allocator = zix_bump_allocator(sizeof(buf), buf);
+  char* const      canonical = zix_canonical_path(&allocator.base, path);
+  return zix_file_type(canonical);
+}
+
+ZixFileType
+zix_symlink_type(const char* const path)
+{
+  return attrs_file_type(GetFileAttributes(path));
+}
+
+ZixStatus
+zix_create_directory(const char* const dir_path)
+{
+  return (!dir_path[0])     ? ZIX_STATUS_BAD_ARG
+         : _mkdir(dir_path) ? zix_errno_status(errno)
+                            : ZIX_STATUS_SUCCESS;
+}
+
+ZixStatus
+zix_create_directory_like(const char* const dir_path,
+                          const char* const existing_path)
+{
+  return (zix_file_type(existing_path) != ZIX_FILE_TYPE_DIRECTORY)
+           ? ZIX_STATUS_NOT_FOUND
+           : zix_create_directory(dir_path);
+}
+
+ZixStatus
+zix_create_symlink(const char* const target_path, const char* const link_path)
+{
+#if USE_CREATESYMBOLICLINK
+  static const DWORD flags = SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE;
+
+  return zix_windows_status(CreateSymbolicLink(link_path, target_path, flags));
+#else
+  return ZIX_STATUS_NOT_SUPPORTED;
+#endif
+}
+
+ZixStatus
+zix_create_directory_symlink(const char* const target_path,
+                             const char* const link_path)
+{
+#if USE_CREATESYMBOLICLINK
+  static const DWORD flags =
+    SYMBOLIC_LINK_FLAG_DIRECTORY | SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE;
+
+  return zix_windows_status(CreateSymbolicLink(link_path, target_path, flags));
+#else
+  return ZIX_STATUS_NOT_SUPPORTED;
+#endif
+}
+
+ZixStatus
+zix_create_hard_link(const char* const target_path, const char* const link_path)
+{
+  return zix_windows_status(CreateHardLink(link_path, target_path, NULL));
+}
+
+char*
+zix_temp_directory_path(ZixAllocator* const allocator)
+{
+  const DWORD size = GetTempPath(0U, NULL);
+  char* const buf  = (char*)zix_calloc(allocator, size, 1);
+  if (buf && (GetTempPath(size, buf) != size - 1U)) {
+    zix_free(allocator, buf);
+    return NULL;
+  }
+
+  return buf;
+}
+
+char*
+zix_current_path(ZixAllocator* const allocator)
+{
+  const DWORD size = GetCurrentDirectory(0U, NULL);
+  char* const buf  = (char*)zix_calloc(allocator, size, 1);
+  if (buf && (GetCurrentDirectory(size, buf) != size - 1U)) {
+    zix_free(allocator, buf);
+    return NULL;
+  }
+
+  return buf;
+}
diff --git a/src/win32/system_win32.c b/src/win32/system_win32.c
new file mode 100644
index 0000000..a2e68bf
--- /dev/null
+++ b/src/win32/system_win32.c
@@ -0,0 +1,20 @@
+// Copyright 2007-2022 David Robillard <d@drobilla.net>
+// SPDX-License-Identifier: ISC
+
+#include "../system.h"
+
+#include <windows.h>
+
+#include <limits.h>
+#include <stdint.h>
+
+uint32_t
+zix_system_page_size(void)
+{
+  SYSTEM_INFO info;
+  GetSystemInfo(&info);
+
+  return (info.dwPageSize > 0 && info.dwPageSize < UINT32_MAX)
+           ? (uint32_t)info.dwPageSize
+           : 512U;
+}