+long sys_ptrace(enum __ptrace_request request, pid_t pid, unsigned long addr, unsigned long data)
+{
+ return syscall(__NR_ptrace, request, pid, (void *)addr, data);
+}
+
+// 33 because of FPSCR
+#define PT_NUM_FPRS (33 * (sizeof(__u64) / sizeof(unsigned long)))
+
+__u64 *peek_fprs(pid_t child)
+{
+ unsigned long *fprs, *p, addr;
+ long ret;
+ int i;
+
+ fprs = malloc(sizeof(unsigned long) * PT_NUM_FPRS);
+ if (!fprs) {
+ perror("malloc() failed");
+ return NULL;
+ }
+
+ for (i = 0, p = fprs; i < PT_NUM_FPRS; i++, p++) {
+ addr = sizeof(unsigned long) * (PT_FPR0 + i);
+ ret = sys_ptrace(PTRACE_PEEKUSER, child, addr, (unsigned long)p);
+ if (ret) {
+ perror("ptrace(PTRACE_PEEKUSR) failed");
+ return NULL;
+ }
+ }
+
+ addr = sizeof(unsigned long) * (PT_FPR0 + i);
+ ret = sys_ptrace(PTRACE_PEEKUSER, child, addr, (unsigned long)&addr);
+ if (!ret) {
+ printf("ptrace(PTRACE_PEEKUSR) succeeded unexpectedly!\n");
+ return NULL;
+ }
+
+ return (__u64 *)fprs;
+}
+
+int poke_fprs(pid_t child, unsigned long *fprs)
+{
+ unsigned long *p, addr;
+ long ret;
+ int i;
+
+ for (i = 0, p = fprs; i < PT_NUM_FPRS; i++, p++) {
+ addr = sizeof(unsigned long) * (PT_FPR0 + i);
+ ret = sys_ptrace(PTRACE_POKEUSER, child, addr, *p);
+ if (ret) {
+ perror("ptrace(PTRACE_POKEUSR) failed");
+ return -1;
+ }
+ }
+
+ addr = sizeof(unsigned long) * (PT_FPR0 + i);
+ ret = sys_ptrace(PTRACE_POKEUSER, child, addr, addr);
+ if (!ret) {
+ printf("ptrace(PTRACE_POKEUSR) succeeded unexpectedly!\n");
+ return -1;
+ }
+
+ return 0;
+}
+