From 06a83491627c5024c374f98a70da81a4e2a473c9 Mon Sep 17 00:00:00 2001
From: Stenzek <stenzek@gmail.com>
Date: Sat, 12 Aug 2023 13:47:08 +1000
Subject: [PATCH] dep/libchdr: Re-add progress precaching

---
 dep/libchdr/include/libchdr/chd.h |  1 +
 dep/libchdr/src/libchdr_chd.c     | 71 ++++++++++++++++++++++---------
 src/util/cd_image_chd.cpp         |  3 +-
 3 files changed, 53 insertions(+), 22 deletions(-)

diff --git a/dep/libchdr/include/libchdr/chd.h b/dep/libchdr/include/libchdr/chd.h
index 160fcb735..e152cf0d3 100644
--- a/dep/libchdr/include/libchdr/chd.h
+++ b/dep/libchdr/include/libchdr/chd.h
@@ -379,6 +379,7 @@ CHD_EXPORT chd_error chd_open(const char *filename, int mode, chd_file *parent,
 
 /* precache underlying file */
 CHD_EXPORT chd_error chd_precache(chd_file *chd);
+CHD_EXPORT chd_error chd_precache_progress(chd_file* chd, void(*progress)(size_t pos, size_t total, void* param), void* param);
 
 /* close a CHD file */
 CHD_EXPORT void chd_close(chd_file *chd);
diff --git a/dep/libchdr/src/libchdr_chd.c b/dep/libchdr/src/libchdr_chd.c
index d2bf4d04e..6d50884a3 100644
--- a/dep/libchdr/src/libchdr_chd.c
+++ b/dep/libchdr/src/libchdr_chd.c
@@ -42,6 +42,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
+#include <limits.h>
 
 #include <libchdr/chd.h>
 #include <libchdr/cdrom.h>
@@ -1733,30 +1734,60 @@ cleanup:
     memory
 -------------------------------------------------*/
 
-CHD_EXPORT chd_error chd_precache(chd_file *chd)
+CHD_EXPORT chd_error chd_precache(chd_file* chd)
 {
-	INT64 count;
-	UINT64 size;
+  return chd_precache_progress(chd, NULL, NULL);
+}
 
-	if (chd->file_cache == NULL)
-	{
-		size = core_fsize(chd->file);
-		if ((INT64)size <= 0)
-			return CHDERR_INVALID_DATA;
-		chd->file_cache = malloc(size);
-		if (chd->file_cache == NULL)
+CHD_EXPORT chd_error chd_precache_progress(chd_file* chd, void(*progress)(size_t pos, size_t total, void* param), void* param)
+{
+#define PRECACHE_CHUNK_SIZE 16 * 1024 * 1024
+
+  size_t count;
+  UINT64 size, done, req_count, last_update_done, update_interval;
+
+  if (chd->file_cache == NULL)
+  {
+    size = core_fsize(chd->file);
+    if ((INT64)size <= 0)
+      return CHDERR_INVALID_DATA;
+
+		if (size > SIZE_MAX)
 			return CHDERR_OUT_OF_MEMORY;
-		core_fseek(chd->file, 0, SEEK_SET);
-		count = core_fread(chd->file, chd->file_cache, size);
-		if (count != size)
-		{
-			free(chd->file_cache);
-			chd->file_cache = NULL;
-			return CHDERR_READ_ERROR;
-		}
-	}
 
-	return CHDERR_NONE;
+    chd->file_cache = malloc(size);
+    if (chd->file_cache == NULL)
+      return CHDERR_OUT_OF_MEMORY;
+    core_fseek(chd->file, 0, SEEK_SET);
+
+		done = 0;
+    last_update_done = 0;
+    update_interval = ((size + 99) / 100);
+
+		while (done < size)
+		{
+			req_count = size - done;
+			if (req_count > PRECACHE_CHUNK_SIZE)
+				req_count = PRECACHE_CHUNK_SIZE;
+
+			count = core_fread(chd->file, chd->file_cache + (size_t)done, (size_t)req_count);
+			if (count != (size_t)req_count)
+			{
+				free(chd->file_cache);
+				chd->file_cache = NULL;
+				return CHDERR_READ_ERROR;
+			}
+
+			done += req_count;
+			if (progress != NULL && (done - last_update_done) >= update_interval && done != size)
+			{
+				last_update_done = done;
+				progress(done, size, param);
+			}
+		}
+  }
+
+  return CHDERR_NONE;
 }
 
 /*-------------------------------------------------
diff --git a/src/util/cd_image_chd.cpp b/src/util/cd_image_chd.cpp
index bf33b6aea..adbfa61bc 100644
--- a/src/util/cd_image_chd.cpp
+++ b/src/util/cd_image_chd.cpp
@@ -320,8 +320,7 @@ CDImage::PrecacheResult CDImageCHD::Precache(ProgressCallback* progress)
     static_cast<ProgressCallback*>(param)->SetProgressValue(std::min<u32>(percent, 100));
   };
 
-  //if (chd_precache_progress(m_chd, callback, progress) != CHDERR_NONE)
-  if (chd_precache(m_chd) != CHDERR_NONE)
+  if (chd_precache_progress(m_chd, callback, progress) != CHDERR_NONE)
     return CDImage::PrecacheResult::ReadError;
 
   m_precached = true;