Fix <sys/resource.h>.

The situation here is a bit confusing. On 64-bit, rlimit and rlimit64 are
the same, and so getrlimit/getrlimit64, setrlimit/setrlimit64,
and prlimit/prlimit64 are all the same. On 32-bit, rlimit and rlimit64 are
different. 32-bit architectures other than MIPS go one step further by having
an even more limited getrlimit system call, so arm and x86 need to use
ugetrlimit instead of getrlimit. Worse, the 32-bit architectures don't have
64-bit getrlimit- and setrlimit-equivalent system calls, and you have to use
prlimit64 instead. There's no 32-bit prlimit system call, so there's no
easy implementation of that --- what should we do if the result of prlimit64
won't fit in a struct rlimit? Since 32-bit survived without prlimit/prlimit64
for this long, I'm not going to bother implementing prlimit for 32-bit.

We need the rlimit64 functions to be able to build strace 4.8 out of the box.

Change-Id: I1903d913b23016a2fc3b9f452885ac730d71e001
diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index d0fa528..6e10daa 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -62,12 +62,21 @@
 int     tgkill(pid_t tgid, pid_t tid, int sig)  all
 int     __ptrace:ptrace(int request, int pid, void* addr, void* data)  all
 int     __set_thread_area:set_thread_area(void*  user_desc)  mips,x86
-int     __getpriority:getpriority(int, int)  all
-int     setpriority(int, int, int)   all
-int     setrlimit(int resource, const struct rlimit* rlp)  all
-int     getrlimit:ugetrlimit(int resource, struct rlimit* rlp)  arm,x86
-int     getrlimit:getrlimit(int resource, struct rlimit* rlp)  aarch64,mips,x86_64
-int     getrusage(int who, struct rusage*  r_usage)  all
+
+# <sys/resource.h>
+int getrusage(int, struct rusage*)  all
+int __getpriority:getpriority(int, int)  all
+int setpriority(int, int, int)   all
+# On LP64, rlimit and rlimit64 are the same.
+# On 32-bit systems we use prlimit64 to implement the rlimit64 functions.
+int getrlimit:ugetrlimit(int, struct rlimit*)  arm,x86
+int getrlimit(int, struct rlimit*)  mips
+int getrlimit|getrlimit64(int, struct rlimit*)  aarch64,x86_64
+int setrlimit(int, const struct rlimit*)  arm,mips,x86
+int setrlimit|setrlimit64(int, const struct rlimit*)  aarch64,x86_64
+int prlimit64|prlimit(pid_t, int, struct rlimit64*, const struct rlimit64*)  aarch64,x86_64
+int prlimit64(pid_t, int, struct rlimit64*, const struct rlimit64*)  arm,mips,x86
+
 int     setgroups:setgroups32(int, const gid_t*)   arm,x86
 int     setgroups:setgroups(int, const gid_t*)     aarch64,mips,x86_64
 int     setpgid(pid_t, pid_t)  all
diff --git a/libc/arch-aarch64/syscalls.mk b/libc/arch-aarch64/syscalls.mk
index 3e5d191..653ef70 100644
--- a/libc/arch-aarch64/syscalls.mk
+++ b/libc/arch-aarch64/syscalls.mk
@@ -123,6 +123,7 @@
 syscall_src += arch-aarch64/syscalls/pipe2.S
 syscall_src += arch-aarch64/syscalls/prctl.S
 syscall_src += arch-aarch64/syscalls/pread64.S
+syscall_src += arch-aarch64/syscalls/prlimit64.S
 syscall_src += arch-aarch64/syscalls/pwrite64.S
 syscall_src += arch-aarch64/syscalls/read.S
 syscall_src += arch-aarch64/syscalls/readahead.S
diff --git a/libc/arch-aarch64/syscalls/getrlimit.S b/libc/arch-aarch64/syscalls/getrlimit.S
index 8b6548f..21b471e 100644
--- a/libc/arch-aarch64/syscalls/getrlimit.S
+++ b/libc/arch-aarch64/syscalls/getrlimit.S
@@ -19,3 +19,6 @@
 
     ret
 END(getrlimit)
+
+    .globl _C_LABEL(getrlimit64)
+    .equ _C_LABEL(getrlimit64), _C_LABEL(getrlimit)
diff --git a/libc/arch-aarch64/syscalls/prlimit64.S b/libc/arch-aarch64/syscalls/prlimit64.S
new file mode 100644
index 0000000..439e355
--- /dev/null
+++ b/libc/arch-aarch64/syscalls/prlimit64.S
@@ -0,0 +1,24 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <private/bionic_asm.h>
+
+ENTRY(prlimit64)
+    stp     x29, x30, [sp, #-16]!
+    mov     x29,  sp
+    str     x8,       [sp, #-16]!
+
+    mov     x8, __NR_prlimit64
+    svc     #0
+
+    ldr     x8,       [sp], #16
+    ldp     x29, x30, [sp], #16
+
+    cmn     x0, #(MAX_ERRNO + 1)
+    cneg    x0, x0, hi
+    b.hi    __set_errno
+
+    ret
+END(prlimit64)
+
+    .globl _C_LABEL(prlimit)
+    .equ _C_LABEL(prlimit), _C_LABEL(prlimit64)
diff --git a/libc/arch-aarch64/syscalls/setrlimit.S b/libc/arch-aarch64/syscalls/setrlimit.S
index 3591a84..e723806 100644
--- a/libc/arch-aarch64/syscalls/setrlimit.S
+++ b/libc/arch-aarch64/syscalls/setrlimit.S
@@ -19,3 +19,6 @@
 
     ret
 END(setrlimit)
+
+    .globl _C_LABEL(setrlimit64)
+    .equ _C_LABEL(setrlimit64), _C_LABEL(setrlimit)
diff --git a/libc/arch-arm/syscalls.mk b/libc/arch-arm/syscalls.mk
index f1763ef..83e6a97 100644
--- a/libc/arch-arm/syscalls.mk
+++ b/libc/arch-arm/syscalls.mk
@@ -129,6 +129,7 @@
 syscall_src += arch-arm/syscalls/pipe2.S
 syscall_src += arch-arm/syscalls/prctl.S
 syscall_src += arch-arm/syscalls/pread64.S
+syscall_src += arch-arm/syscalls/prlimit64.S
 syscall_src += arch-arm/syscalls/pwrite64.S
 syscall_src += arch-arm/syscalls/read.S
 syscall_src += arch-arm/syscalls/readahead.S
diff --git a/libc/arch-arm/syscalls/prlimit64.S b/libc/arch-arm/syscalls/prlimit64.S
new file mode 100644
index 0000000..8d9c4ff
--- /dev/null
+++ b/libc/arch-arm/syscalls/prlimit64.S
@@ -0,0 +1,14 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <private/bionic_asm.h>
+
+ENTRY(prlimit64)
+    mov     ip, r7
+    ldr     r7, =__NR_prlimit64
+    swi     #0
+    mov     r7, ip
+    cmn     r0, #(MAX_ERRNO + 1)
+    bxls    lr
+    neg     r0, r0
+    b       __set_errno
+END(prlimit64)
diff --git a/libc/arch-mips/syscalls.mk b/libc/arch-mips/syscalls.mk
index cc7e557..8d87b29 100644
--- a/libc/arch-mips/syscalls.mk
+++ b/libc/arch-mips/syscalls.mk
@@ -129,6 +129,7 @@
 syscall_src += arch-mips/syscalls/pipe2.S
 syscall_src += arch-mips/syscalls/prctl.S
 syscall_src += arch-mips/syscalls/pread64.S
+syscall_src += arch-mips/syscalls/prlimit64.S
 syscall_src += arch-mips/syscalls/pwrite64.S
 syscall_src += arch-mips/syscalls/read.S
 syscall_src += arch-mips/syscalls/readahead.S
diff --git a/libc/arch-mips/syscalls/prlimit64.S b/libc/arch-mips/syscalls/prlimit64.S
new file mode 100644
index 0000000..17e9157
--- /dev/null
+++ b/libc/arch-mips/syscalls/prlimit64.S
@@ -0,0 +1,23 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <asm/unistd.h>
+    .text
+    .globl prlimit64
+    .align 4
+    .ent prlimit64
+
+prlimit64:
+    .set noreorder
+    .cpload $t9
+    li $v0, __NR_prlimit64
+    syscall
+    bnez $a3, 1f
+    move $a0, $v0
+    j $ra
+    nop
+1:
+    la $t9,__set_errno
+    j $t9
+    nop
+    .set reorder
+    .end prlimit64
diff --git a/libc/arch-x86/syscalls.mk b/libc/arch-x86/syscalls.mk
index 0699d09..b7d1e08 100644
--- a/libc/arch-x86/syscalls.mk
+++ b/libc/arch-x86/syscalls.mk
@@ -128,6 +128,7 @@
 syscall_src += arch-x86/syscalls/pipe2.S
 syscall_src += arch-x86/syscalls/prctl.S
 syscall_src += arch-x86/syscalls/pread64.S
+syscall_src += arch-x86/syscalls/prlimit64.S
 syscall_src += arch-x86/syscalls/pwrite64.S
 syscall_src += arch-x86/syscalls/read.S
 syscall_src += arch-x86/syscalls/readahead.S
diff --git a/libc/arch-x86/syscalls/prlimit64.S b/libc/arch-x86/syscalls/prlimit64.S
new file mode 100644
index 0000000..2256425
--- /dev/null
+++ b/libc/arch-x86/syscalls/prlimit64.S
@@ -0,0 +1,34 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <private/bionic_asm.h>
+
+ENTRY(prlimit64)
+    pushl   %ebx
+    pushl   %ecx
+    pushl   %edx
+    pushl   %esi
+    .cfi_def_cfa_offset 16
+    .cfi_rel_offset ebx, 0
+    .cfi_rel_offset ecx, 4
+    .cfi_rel_offset edx, 8
+    .cfi_rel_offset esi, 12
+    mov     20(%esp), %ebx
+    mov     24(%esp), %ecx
+    mov     28(%esp), %edx
+    mov     32(%esp), %esi
+    movl    $__NR_prlimit64, %eax
+    int     $0x80
+    cmpl    $-MAX_ERRNO, %eax
+    jb      1f
+    negl    %eax
+    pushl   %eax
+    call    __set_errno
+    addl    $4, %esp
+    orl     $-1, %eax
+1:
+    popl    %esi
+    popl    %edx
+    popl    %ecx
+    popl    %ebx
+    ret
+END(prlimit64)
diff --git a/libc/arch-x86_64/syscalls.mk b/libc/arch-x86_64/syscalls.mk
index cac7423..ec09e77 100644
--- a/libc/arch-x86_64/syscalls.mk
+++ b/libc/arch-x86_64/syscalls.mk
@@ -124,6 +124,7 @@
 syscall_src += arch-x86_64/syscalls/pipe2.S
 syscall_src += arch-x86_64/syscalls/prctl.S
 syscall_src += arch-x86_64/syscalls/pread64.S
+syscall_src += arch-x86_64/syscalls/prlimit64.S
 syscall_src += arch-x86_64/syscalls/pwrite64.S
 syscall_src += arch-x86_64/syscalls/read.S
 syscall_src += arch-x86_64/syscalls/readahead.S
diff --git a/libc/arch-x86_64/syscalls/getrlimit.S b/libc/arch-x86_64/syscalls/getrlimit.S
index 1417b28..0b3536c 100644
--- a/libc/arch-x86_64/syscalls/getrlimit.S
+++ b/libc/arch-x86_64/syscalls/getrlimit.S
@@ -14,3 +14,6 @@
 1:
     ret
 END(getrlimit)
+
+    .globl _C_LABEL(getrlimit64)
+    .equ _C_LABEL(getrlimit64), _C_LABEL(getrlimit)
diff --git a/libc/arch-x86_64/syscalls/prlimit64.S b/libc/arch-x86_64/syscalls/prlimit64.S
new file mode 100644
index 0000000..b451e8f
--- /dev/null
+++ b/libc/arch-x86_64/syscalls/prlimit64.S
@@ -0,0 +1,20 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <private/bionic_asm.h>
+
+ENTRY(prlimit64)
+    movq    %rcx, %r10
+    movl    $__NR_prlimit64, %eax
+    syscall
+    cmpq    $-MAX_ERRNO, %rax
+    jb      1f
+    negl    %eax
+    movl    %eax, %edi
+    call    __set_errno
+    orq     $-1, %rax
+1:
+    ret
+END(prlimit64)
+
+    .globl _C_LABEL(prlimit)
+    .equ _C_LABEL(prlimit), _C_LABEL(prlimit64)
diff --git a/libc/arch-x86_64/syscalls/setrlimit.S b/libc/arch-x86_64/syscalls/setrlimit.S
index de5b3b7..e445ec0 100644
--- a/libc/arch-x86_64/syscalls/setrlimit.S
+++ b/libc/arch-x86_64/syscalls/setrlimit.S
@@ -14,3 +14,6 @@
 1:
     ret
 END(setrlimit)
+
+    .globl _C_LABEL(setrlimit64)
+    .equ _C_LABEL(setrlimit64), _C_LABEL(setrlimit)
diff --git a/libc/bionic/legacy_32_bit_support.cpp b/libc/bionic/legacy_32_bit_support.cpp
index 884dd8b..d7ccdb9 100644
--- a/libc/bionic/legacy_32_bit_support.cpp
+++ b/libc/bionic/legacy_32_bit_support.cpp
@@ -28,10 +28,9 @@
 
 #include <errno.h>
 #include <stdarg.h>
+#include <sys/resource.h>
 #include <sys/types.h>
 #include <sys/vfs.h>
-#include <sys/vfs.h>
-#include <unistd.h>
 #include <unistd.h>
 
 #if __LP64__
@@ -86,3 +85,13 @@
 ssize_t pwrite(int fd, const void* buf, size_t byte_count, off_t offset) {
   return pwrite64(fd, buf, byte_count, static_cast<off64_t>(offset));
 }
+
+// There is no getrlimit64 system call, so we need to use prlimit64.
+int getrlimit64(int resource, rlimit64* limits64) {
+  return prlimit64(0, resource, NULL, limits64);
+}
+
+// There is no setrlimit64 system call, so we need to use prlimit64.
+int setrlimit64(int resource, const rlimit64* limits64) {
+  return prlimit64(0, resource, limits64, NULL);
+}
diff --git a/libc/include/sys/resource.h b/libc/include/sys/resource.h
index ef325c7..a91fa53 100644
--- a/libc/include/sys/resource.h
+++ b/libc/include/sys/resource.h
@@ -25,30 +25,35 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_RESOURCE_H_
 #define _SYS_RESOURCE_H_
 
 #include <sys/cdefs.h>
-#include <sys/types.h>     /* MUST be included before linux/resource.h */
+#include <sys/types.h>
 
-/* TRICK AHEAD: <linux/resource.h> defines a getrusage function with
- *              a non-standard signature. this is surprising because the
- *              syscall seems to use the standard one instead.
- *              once again, creative macro usage saves the days
- */
-#define  getrusage   __kernel_getrusage
 #include <linux/resource.h>
-#undef   getrusage
-
-typedef unsigned long rlim_t;
 
 __BEGIN_DECLS
 
+typedef unsigned long rlim_t;
+
+extern int getrlimit(int, struct rlimit*);
+extern int setrlimit(int, const struct rlimit*);
+
+extern int getrlimit64(int, struct rlimit64*);
+extern int setrlimit64(int, const struct rlimit64*);
+
 extern int getpriority(int, int);
 extern int setpriority(int, int, int);
-extern int getrlimit(int resource, struct rlimit *rlp);
-extern int setrlimit(int resource, const struct rlimit *rlp);
-extern int getrusage(int  who, struct rusage*  r_usage);
+
+extern int getrusage(int, struct rusage*);
+
+#if __LP64__
+/* Implementing prlimit for 32-bit isn't worth the effort. */
+extern int prlimit(pid_t, int, const struct rlimit*, struct rlimit*);
+#endif
+extern int prlimit64(pid_t, int, const struct rlimit64*, struct rlimit64*);
 
 __END_DECLS