diff options
| author | Michael Smith <mikesmiffy128@gmail.com> | 2024-08-22 01:09:35 +0100 |
|---|---|---|
| committer | Michael Smith <mikesmiffy128@gmail.com> | 2024-08-23 20:57:56 +0100 |
| commit | 0ad204f21940745c35a665e3f367b9331322c3f4 (patch) | |
| tree | 3560a73e99b0f5d70d409e569bd5f4176ec60914 | |
| parent | 484b72706964e05d15b3c0e114ea0502ba4a07db (diff) | |
Add a quick hack fix for Portal 4104 demo playback
Thanks Evan Lin for doing the hard RE work to figure out the necessary
patch - I just reimplemented that here in about the dumbest way
possible.
| -rw-r--r-- | src/fixes.c | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/src/fixes.c b/src/fixes.c index 226c5a9..3359854 100644 --- a/src/fixes.c +++ b/src/fixes.c @@ -15,7 +15,6 @@ * PERFORMANCE OF THIS SOFTWARE. */ -#include <stdlib.h> #include <string.h> #ifdef _WIN32 @@ -23,8 +22,13 @@ #endif #include "con_.h" +#include "errmsg.h" #include "gametype.h" #include "langext.h" +#include "mem.h" +#include "os.h" +#include "ppmagic.h" +#include "sst.h" static void chflags(const char *name, int unset, int set) { struct con_var *v = con_findvar(name); @@ -181,10 +185,35 @@ static void l4d1specific(void) { chcmdflags("update_addon_paths", 0, CON_CCMDEXEC); } +static void portal1specific(void) { +#ifdef _WIN32 + // TODO(compat): this is an absolutely atrocious way to implement this. it + // should only be temporary in the interests of getting 4104 working right + // away. since other versions also have broken demos, a more general fix + // should be done... eventually... + void *EyeAngles = mem_offset(clientlib, 0x19D1B0); // in C_PortalPlayer + static const char match[] = + HEXBYTES(56, 8B, F1, E8, 48, 50, EA, FF, 84, C0, 74, 25); + if (!memcmp(EyeAngles, match, sizeof(match))) { + char *patch = mem_offset(EyeAngles, 39); + if (patch[0] == 0x75 && patch[1] == 0x08) { + if_hot (os_mprot(patch, 2, PAGE_EXECUTE_READWRITE)) { + patch[0] = 0x90; patch[1] = 0x90; // replace je with nop + } + else { + errmsg_warnsys("unable to fix 4104 demo playback bug: " + "couldn't make memory writable"); + } + } + } +#endif +} + void fixes_apply(void) { generalfixes(); if (GAMETYPE_MATCHES(L4D1)) l4d1specific(); else if (GAMETYPE_MATCHES(L4D2x)) l4d2specific(); + else if (GAMETYPE_MATCHES(Portal1)) portal1specific(); } // vi: sw=4 ts=4 noet tw=80 cc=80 |