initial upload

src/path/path.c

@@ -0,0 +1,167 @@
+// Copyright (c) 2024 Epic Games Tools
+// Licensed under the MIT license (https://opensource.org/license/mit/)
+
+////////////////////////////////
+//~ allen: Path Helper Functions
+
+internal StringMatchFlags
+path_match_flags_from_os(OperatingSystem os)
+{
+  StringMatchFlags flags = StringMatchFlag_SlashInsensitive;
+  switch(os)
+  {
+    default:{}break;
+    case OperatingSystem_Windows:
+    {
+      flags |= StringMatchFlag_CaseInsensitive;
+    }break;
+    case OperatingSystem_Linux:
+    case OperatingSystem_Mac:
+    {
+      // NOTE(rjf): no-op
+    }break;
+  }
+  return flags;
+}
+
+internal String8
+path_relative_dst_from_absolute_dst_src(Arena *arena, String8 dst, String8 src)
+{
+  Temp scratch = scratch_begin(&arena, 1);
+  
+  // rjf: gather path parts
+  String8 dst_name = str8_skip_last_slash(dst);
+  String8 src_folder = str8_chop_last_slash(src);
+  String8 dst_folder = str8_chop_last_slash(dst);
+  String8List src_folders = str8_split_path(scratch.arena, src_folder);
+  String8List dst_folders = str8_split_path(scratch.arena, dst_folder);
+  
+  // rjf: count # of backtracks to get from src -> dest
+  U64 num_backtracks = src_folders.node_count;
+  for(String8Node *src_n = src_folders.first, *bp_n = dst_folders.first;
+      src_n != 0 && bp_n != 0;
+      src_n = src_n->next, bp_n = bp_n->next)
+  {
+    if(str8_match(src_n->string, bp_n->string, path_match_flags_from_os(operating_system_from_context())))
+    {
+      num_backtracks -= 1;
+    }
+    else
+    {
+      break;
+    }
+  }
+  
+  // rjf: only build relative string if # of backtracks is not the entire `src`.
+  // if getting to `dst` from `src` requires erasing the entire `src`, then the
+  // only possible way to get to `dst` from `src` is via absolute path.
+  String8 dst_path = {0};
+  if(num_backtracks >= src_folders.node_count)
+  {
+    dst_path = path_normalized_from_string(arena, dst);
+  }
+  else
+  {
+    // rjf: build backtrack parts
+    String8List dst_path_strs = {0};
+    for(U64 idx = 0; idx < num_backtracks; idx += 1)
+    {
+      str8_list_push(scratch.arena, &dst_path_strs, str8_lit(".."));
+    }
+    
+    // rjf: build parts of dst which are unique from src
+    {
+      B32 unique_from_src = 0;
+      for(String8Node *src_n = src_folders.first, *bp_n = dst_folders.first;
+          bp_n != 0;
+          bp_n = bp_n->next)
+      {
+        if(!unique_from_src && (src_n == 0 || !str8_match(src_n->string, bp_n->string, path_match_flags_from_os(operating_system_from_context()))))
+        {
+          unique_from_src = 1;
+        }
+        if(unique_from_src)
+        {
+          str8_list_push(scratch.arena, &dst_path_strs, bp_n->string);
+        }
+        if(src_n != 0)
+        {
+          src_n = src_n->next;
+        }
+      }
+    }
+    
+    // rjf: build file name
+    str8_list_push(scratch.arena, &dst_path_strs, dst_name);
+    
+    // rjf: join
+    StringJoin join = {0};
+    {
+      join.sep = str8_lit("/");
+    }
+    dst_path = str8_list_join(arena, &dst_path_strs, &join);
+  }
+  scratch_end(scratch);
+  return dst_path;
+}
+
+internal String8
+path_absolute_dst_from_relative_dst_src(Arena *arena, String8 dst, String8 src)
+{
+  String8 result = dst;
+  PathStyle dst_style = path_style_from_str8(dst);
+  if(dst_style == PathStyle_Relative)
+  {
+    Temp scratch = scratch_begin(&arena, 1);
+    String8 dst_from_src_absolute = push_str8f(scratch.arena, "%S/%S", src, dst);
+    String8 dst_from_src_absolute_normalized = path_normalized_from_string(arena, dst_from_src_absolute);
+    result = dst_from_src_absolute_normalized;
+    scratch_end(scratch);
+  }
+  return result;
+}
+
+internal String8List
+path_normalized_list_from_string(Arena *arena, String8 path_string, PathStyle *style_out){
+  // analyze path
+  PathStyle path_style = path_style_from_str8(path_string);
+  String8List path = str8_split_path(arena, path_string);
+  
+  // prepend current path to convert relative -> absolute
+  PathStyle path_style_full = path_style;
+  if (path.node_count != 0 && path_style == PathStyle_Relative){
+    String8List current_path_strs = {0};
+    os_string_list_from_system_path(arena, OS_SystemPath_Current, &current_path_strs);
+    String8 current_path_string = str8_list_first(&current_path_strs);
+    
+    PathStyle current_path_style = path_style_from_str8(current_path_string);
+    Assert(current_path_style != PathStyle_Relative);
+    
+    String8List current_path = str8_split_path(arena, current_path_string);
+    str8_list_concat_in_place(&current_path, &path);
+    path = current_path;
+    path_style_full = current_path_style;
+  }
+  
+  // resolve dots
+  str8_path_list_resolve_dots_in_place(&path, path_style_full);
+  
+  // return
+  if (style_out != 0){
+    *style_out = path_style_full;
+  }
+  return(path);
+}
+
+internal String8
+path_normalized_from_string(Arena *arena, String8 path_string){
+  Temp scratch = scratch_begin(&arena, 1);
+  
+  PathStyle style = PathStyle_Relative;
+  String8List path = path_normalized_list_from_string(scratch.arena, path_string, &style);
+  
+  String8 result = str8_path_list_join_by_style(arena, &path, style);
+  scratch_end(scratch);
+  return(result);
+}
+

src/path/path.h

@@ -0,0 +1,16 @@
+// Copyright (c) 2024 Epic Games Tools
+// Licensed under the MIT license (https://opensource.org/license/mit/)
+
+#ifndef PATH_H
+#define PATH_H
+
+////////////////////////////////
+//~ allen: Path Helper Functions
+
+internal StringMatchFlags path_match_flags_from_os(OperatingSystem os);
+internal String8 path_relative_dst_from_absolute_dst_src(Arena *arena, String8 dst, String8 src);
+internal String8 path_absolute_dst_from_relative_dst_src(Arena *arena, String8 dst, String8 src);
+internal String8List path_normalized_list_from_string(Arena *arena, String8 path, PathStyle *style_out);
+internal String8 path_normalized_from_string(Arena *arena, String8 path);
+
+#endif //PATH_H