Replace 'struct ucontext' with 'ucontext_t' type

glibc used to have:

   typedef struct ucontext { ... } ucontext_t;

glibc now has:

   typedef struct ucontext_t { ... } ucontext_t;

(See https://sourceware.org/bugzilla/show_bug.cgi?id=21457
 for detail and rationale for the glibc change)

However, QEMU used "struct ucontext" in declarations. This is a
private name and compatibility cannot be guaranteed. Switch to
only using the standardized type name.

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Message-id: 20170628204452.41230-1-raj.khem@gmail.com
Cc: Kamil Rytarowski <kamil@netbsd.org>
Cc: Riku Voipio <riku.voipio@iki.fi>
Cc: Laurent Vivier <laurent@vivier.eu>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[PMM: Rewrote commit message, based mostly on the one from
 Nathaniel McCallum]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

linux-user/host/aarch64/hostdep.h

@@ -24,7 +24,7 @@ extern char safe_syscall_end[];
 /* Adjust the signal context to rewind out of safe-syscall if we're in it */
 static inline void rewind_if_in_safe_syscall(void *puc)
 {
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     __u64 *pcreg = &uc->uc_mcontext.pc;
 
     if (*pcreg > (uintptr_t)safe_syscall_start

linux-user/host/arm/hostdep.h

@@ -24,7 +24,7 @@ extern char safe_syscall_end[];
 /* Adjust the signal context to rewind out of safe-syscall if we're in it */
 static inline void rewind_if_in_safe_syscall(void *puc)
 {
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     unsigned long *pcreg = &uc->uc_mcontext.arm_pc;
 
     if (*pcreg > (uintptr_t)safe_syscall_start

linux-user/host/i386/hostdep.h

@@ -24,7 +24,7 @@ extern char safe_syscall_end[];
 /* Adjust the signal context to rewind out of safe-syscall if we're in it */
 static inline void rewind_if_in_safe_syscall(void *puc)
 {
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     greg_t *pcreg = &uc->uc_mcontext.gregs[REG_EIP];
 
     if (*pcreg > (uintptr_t)safe_syscall_start

linux-user/host/ppc64/hostdep.h

@@ -24,7 +24,7 @@ extern char safe_syscall_end[];
 /* Adjust the signal context to rewind out of safe-syscall if we're in it */
 static inline void rewind_if_in_safe_syscall(void *puc)
 {
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     unsigned long *pcreg = &uc->uc_mcontext.gp_regs[PT_NIP];
 
     if (*pcreg > (uintptr_t)safe_syscall_start

linux-user/host/s390x/hostdep.h

@@ -24,7 +24,7 @@ extern char safe_syscall_end[];
 /* Adjust the signal context to rewind out of safe-syscall if we're in it */
 static inline void rewind_if_in_safe_syscall(void *puc)
 {
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     unsigned long *pcreg = &uc->uc_mcontext.psw.addr;
 
     if (*pcreg > (uintptr_t)safe_syscall_start

linux-user/host/x86_64/hostdep.h

@@ -24,7 +24,7 @@ extern char safe_syscall_end[];
 /* Adjust the signal context to rewind out of safe-syscall if we're in it */
 static inline void rewind_if_in_safe_syscall(void *puc)
 {
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     greg_t *pcreg = &uc->uc_mcontext.gregs[REG_RIP];
 
     if (*pcreg > (uintptr_t)safe_syscall_start

linux-user/signal.c

@@ -3346,7 +3346,7 @@ static void setup_rt_frame(int sig, struct target_sigaction *ka,
     *
     *   a0 = signal number
     *   a1 = pointer to siginfo_t
-    *   a2 = pointer to struct ucontext
+    *   a2 = pointer to ucontext_t
     *
     * $25 and PC point to the signal handler, $29 points to the
     * struct sigframe.
@@ -3764,7 +3764,7 @@ struct target_signal_frame {
 
 struct rt_signal_frame {
     siginfo_t info;
-    struct ucontext uc;
+    ucontext_t uc;
     uint32_t tramp[2];
 };
 
@@ -3980,7 +3980,7 @@ struct rt_signal_frame {
     siginfo_t *pinfo;
     void *puc;
     siginfo_t info;
-    struct ucontext uc;
+    ucontext_t uc;
     uint16_t retcode[4];      /* Trampoline code. */
 };
 
@@ -4515,7 +4515,7 @@ static void setup_rt_frame(int sig, struct target_sigaction *ka,
         tswap_siginfo(&frame->info, info);
     }
 
-    /*err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));*/
+    /*err |= __clear_user(&frame->uc, offsetof(ucontext_t, uc_mcontext));*/
     __put_user(0, &frame->uc.tuc_flags);
     __put_user(0, &frame->uc.tuc_link);
     __put_user(target_sigaltstack_used.ss_sp,
@@ -5007,7 +5007,7 @@ enum {
 
 struct target_ucontext {
     target_ulong tuc_flags;
-    target_ulong tuc_link;    /* struct ucontext __user * */
+    target_ulong tuc_link;    /* ucontext_t __user * */
     struct target_sigaltstack tuc_stack;
 #if !defined(TARGET_PPC64)
     int32_t tuc_pad[7];

tests/tcg/test-i386.c

@@ -1720,7 +1720,7 @@ int tab[2];
 
 void sig_handler(int sig, siginfo_t *info, void *puc)
 {
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
 
     printf("si_signo=%d si_errno=%d si_code=%d",
            info->si_signo, info->si_errno, info->si_code);
@@ -1912,7 +1912,7 @@ void test_exceptions(void)
 /* specific precise single step test */
 void sig_trap_handler(int sig, siginfo_t *info, void *puc)
 {
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     printf("EIP=" FMTLX "\n", (long)uc->uc_mcontext.gregs[REG_EIP]);
 }
 

user-exec.c

@@ -167,7 +167,7 @@ int cpu_signal_handler(int host_signum, void *pinfo,
 #elif defined(__OpenBSD__)
     struct sigcontext *uc = puc;
 #else
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
 #endif
     unsigned long pc;
     int trapno;
@@ -222,7 +222,7 @@ int cpu_signal_handler(int host_signum, void *pinfo,
 #elif defined(__OpenBSD__)
     struct sigcontext *uc = puc;
 #else
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
 #endif
 
     pc = PC_sig(uc);
@@ -289,7 +289,7 @@ int cpu_signal_handler(int host_signum, void *pinfo,
 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
     ucontext_t *uc = puc;
 #else
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
 #endif
     unsigned long pc;
     int is_write;
@@ -316,7 +316,7 @@ int cpu_signal_handler(int host_signum, void *pinfo,
                            void *puc)
 {
     siginfo_t *info = pinfo;
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     uint32_t *pc = uc->uc_mcontext.sc_pc;
     uint32_t insn = *pc;
     int is_write = 0;
@@ -414,7 +414,7 @@ int cpu_signal_handler(int host_signum, void *pinfo,
 #if defined(__NetBSD__)
     ucontext_t *uc = puc;
 #else
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
 #endif
     unsigned long pc;
     int is_write;
@@ -441,7 +441,7 @@ int cpu_signal_handler(int host_signum, void *pinfo,
 int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
 {
     siginfo_t *info = pinfo;
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     uintptr_t pc = uc->uc_mcontext.pc;
     uint32_t insn = *(uint32_t *)pc;
     bool is_write;
@@ -474,7 +474,7 @@ int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
 int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
 {
     siginfo_t *info = pinfo;
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     unsigned long ip;
     int is_write = 0;
 
@@ -505,7 +505,7 @@ int cpu_signal_handler(int host_signum, void *pinfo,
                        void *puc)
 {
     siginfo_t *info = pinfo;
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     unsigned long pc;
     uint16_t *pinsn;
     int is_write = 0;
@@ -558,7 +558,7 @@ int cpu_signal_handler(int host_signum, void *pinfo,
                        void *puc)
 {
     siginfo_t *info = pinfo;
-    struct ucontext *uc = puc;
+    ucontext_t *uc = puc;
     greg_t pc = uc->uc_mcontext.pc;
     int is_write;