Add ALSA ioctls PVERSION and CARD_INFO to record_syscall

VMware Workstation needs to query ALSA for information about
the system's audio devices to allow users to select which device
to direct VM audio output to. When running rr against Workstation,
I found rr asserting around ioctls SNDRV_CTL_IOCTL_PVERSION and
SNDRV_CTL_IOCTL_CARD_INFO.

This patch is my total wild guess on how to patch around this
problem. It's enough to launch Workstation and have it running
under rr, but I cannot attest to its correctness.

CMakeLists.txt

@@ -304,6 +304,7 @@ set(BASIC_TESTS
   accept
   alarm
   alarm2
+  alsa_ioctl
   arch_prctl
   async_segv_ignored
   async_signal_syscalls2

LICENSE

@@ -1,6 +1,8 @@
 Copyright (c) 2013 Mozilla Foundation
+Copyright 2015 VMware, Inc
 
 Contributors: Albert Noll <noll.albert@gmail.com>, Thomas Anderegg <thomas@tanderegg.com>, Nimrod Partush <nimrodpar@gmail.com>
+              Andrew Walton <awalton@vmware.com>
 
 Permission is hereby granted, free of charge, to any person obtaining a
 copy of this software and associated documentation files (the "Software"),

src/kernel_abi.h

@@ -29,6 +29,7 @@
 #include <signal.h>
 #include <stddef.h>
 #include <stdint.h>
+#include <sound/asound.h>
 #include <sys/epoll.h>
 #include <sys/ioctl.h>
 #include <sys/quota.h>
@@ -1166,6 +1167,19 @@ struct BaseArch : public wordsize, public FcntlConstants {
     ptr<robust_list> list_op_pending;
   };
   RR_VERIFY_TYPE(robust_list_head);
+
+  struct snd_ctl_card_info {
+    int card;
+    int pad;
+    unsigned char id[16];
+    unsigned char driver[16];
+    unsigned char name[32];
+    unsigned char longname[80];
+    unsigned char reserved_[16];
+    unsigned char mixername[80];
+    unsigned char components[128];
+  };
+  RR_VERIFY_TYPE(snd_ctl_card_info);
 };
 
 struct X86Arch : public BaseArch<SupportedArch::x86, WordSize32Defs> {

src/record_syscall.cc

@@ -29,6 +29,7 @@
 #include <linux/msdos_fs.h>
 #include <poll.h>
 #include <sched.h>
+#include <sound/asound.h>
 #include <sys/epoll.h>
 #include <sys/ioctl.h>
 #include <sys/mman.h>
@@ -1180,6 +1181,14 @@ static Switchable prepare_ioctl(Task* t, TaskSyscallState& syscall_state) {
     case TIOCGWINSZ:
       syscall_state.reg_parameter<typename Arch::winsize>(3);
       return PREVENT_SWITCH;
+
+    case SNDRV_CTL_IOCTL_PVERSION:
+      syscall_state.reg_parameter<int>(3);
+      return PREVENT_SWITCH;
+
+    case SNDRV_CTL_IOCTL_CARD_INFO:
+      syscall_state.reg_parameter<typename Arch::snd_ctl_card_info>(3);
+      return PREVENT_SWITCH;
   }
 
   /* In ioctl language, "_IOC_READ" means "outparam".  Both

src/test/alsa_ioctl.c

@@ -0,0 +1,32 @@
+/* -*- Mode: C; tab-width: 8; c-basic-offset: 2; indent-tabs-mode: nil; -*- */
+
+#include "rrutil.h"
+
+#ifndef ALSA_DEVICE_DIRECTORY
+#define ALSA_DEVICE_DIRECTORY "/dev/snd/"
+#endif
+
+int main(int argc, char* argv[]) {
+  int fd = open(ALSA_DEVICE_DIRECTORY "control0", O_NONBLOCK | O_RDONLY);
+  if (fd < 0) {
+    test_assert(errno == EACCES || errno == ENOENT);
+  } else {
+    int* pversion;
+    struct snd_ctl_card_info* info;
+
+    ALLOCATE_GUARD(pversion, 'x');
+    *pversion = -1;
+    test_assert(0 == ioctl(fd, SNDRV_CTL_IOCTL_PVERSION, pversion));
+    VERIFY_GUARD(pversion);
+    test_assert(pversion >= 0);
+
+    ALLOCATE_GUARD(info, 1);
+    test_assert(0 == ioctl(fd, SNDRV_CTL_IOCTL_CARD_INFO, info));
+    VERIFY_GUARD(info);
+    test_assert(info->id[0] > 1);
+    test_assert(info->driver[0] > 1);
+  }
+
+  atomic_puts("EXIT-SUCCESS");
+  return 0;
+}

src/test/rrutil.h

@@ -31,6 +31,7 @@
 #include <pty.h>
 #include <sched.h>
 #include <signal.h>
+#include <sound/asound.h>
 #include <stdarg.h>
 #include <stddef.h>
 #include <stdint.h>