feat(iidx19): imagefs override strategy with local file redir

src/imports/avs.h

@@ -231,6 +231,7 @@ void property_node_datasize(struct property_node *node);
 bool std_getenv(const char *key, char *val, uint32_t nbytes);
 void std_setenv(const char *key, const char *val);
 
+void* avs_fs_open(const char* path, int mode, int flags);
 int avs_fs_addfs(void *filesys_struct);
 int avs_fs_mount(
     const char *mountpoint, const char *fsroot, const char *fstype, void *data);

src/imports/import_32_1304_avs.def

@@ -2,6 +2,7 @@ LIBRARY libavs-win32
 
 EXPORTS
     avs_boot @237 NONAME
+    avs_fs_open @178 NONAME
     avs_net_ctrl @15 NONAME
     avs_shutdown @333 NONAME
     avs_thread_create @183 NONAME
@@ -25,4 +26,4 @@ EXPORTS
     property_read_query_memsize @100 NONAME
     property_search @244 NONAME
     std_getenv @226 NONAME
-    std_setenv  @114 NONAME
+    std_setenv @114 NONAME

src/main/iidxhook5/Module.mk

@@ -25,3 +25,4 @@ libs_iidxhook5      := \
 
 src_iidxhook5       := \
     dllmain.c \
+    ifs-snd-redir.c \

src/main/iidxhook5/dllmain.c

@@ -40,6 +40,8 @@
 #include "util/str.h"
 #include "util/thread.h"
 
+#include "ifs-snd-redir.h"
+
 #define IIDXHOOK5_INFO_HEADER \
     "iidxhook for Lincle"     \
     ", build " __DATE__ " " __TIME__ ", gitrev " STRINGIFY(GITREV)
@@ -179,6 +181,8 @@ static bool my_dll_entry_init(char *sidcode, struct property_node *param)
         ezusb2_emu_device_hook_init(ezusb2_iidx_emu_msg_init());
     }
 
+    iidxhook5_ifs_snd_redir_init();
+
     /* Card reader emulation, same issue with hooking as IO emulation */
     rs232_hook_init();
 

src/main/iidxhook5/ifs-snd-redir.c

@@ -0,0 +1,64 @@
+#define LOG_MODULE "ifs-snd-redir"
+
+#include <stdint.h>
+#include <string.h>
+
+#include "hook/table.h"
+
+#include "imports/avs.h"
+
+#include "iidxhook5/ifs-snd-redir.h"
+
+#include "util/log.h"
+#include "util/str.h"
+
+static void* (*real_avs_fs_open)(const char* path, int mode, int flags);
+static void* my_avs_fs_open(const char* path, int mode, int flags);
+
+static const struct hook_symbol iidxhook5_ifs_snd_redir_hook_syms[] = {
+    {.name = "XC058ba50000b6", // avs_fs_open
+     .patch = my_avs_fs_open,
+     .link = (void **) &real_avs_fs_open},
+};
+
+static void* my_avs_fs_open(const char* path, int mode, int flags)
+{
+    void* handle;
+    char redir_path[MAX_PATH];
+
+    // Trap virtual path /sd00/*, /sd01/*, /sd02/*, /sd03/* that contain
+    // sound data that is stored in ifs files in data/imagefs
+    // Create a generice override strategy by redirecting to local folder
+    // /sound/*. Check if open succeeds and return that. Otherwise, stay on
+    // imagefs path to stay compatible with stock data.
+
+    if (!strncmp(path, "/sd0", 4)) {
+        strcpy(redir_path, "/data/sound");
+        strcat(redir_path, &path[5]);
+
+        log_misc("Sound data redirect: %s -> %s", path, redir_path);
+
+        handle = real_avs_fs_open(redir_path, mode, flags);
+
+        if (handle != NULL) {
+            log_misc("Success, use %s", redir_path);
+            return handle;
+        } else {
+            log_misc("Failure, use %s", path);
+            return real_avs_fs_open(path, mode, flags);
+        }
+    }
+
+    return real_avs_fs_open(path, mode, flags);
+}
+
+void iidxhook5_ifs_snd_redir_init()
+{
+    hook_table_apply(
+        NULL,
+        "libavs-win32.dll",
+        iidxhook5_ifs_snd_redir_hook_syms,
+        lengthof(iidxhook5_ifs_snd_redir_hook_syms));
+
+    log_info("Inserted ifs-snd-redir hooks");
+}

src/main/iidxhook5/ifs-snd-redir.h

@@ -0,0 +1,12 @@
+#ifndef IIDXHOOK5_IFS_SND_REDIR_H
+#define IIDXHOOK5_IFS_SND_REDIR_H
+
+/**
+ * Redirect any reads from the ifs files in data/imagefs that contain
+ * sound data to local files in data/sound. Required to enable bemanitools
+ * monitor-check feature to trap open calls to all sound data and apply
+ * different monitor refresh values.
+ */
+void iidxhook5_ifs_snd_redir_init();
+
+#endif