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ack/plat/linuxppc/libsys/sigaction.s

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Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
#define __NR_sigaction 67
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
#define __NR_sigprocmask 126
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
#define SIG_SETMASK 2
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
/* offsets into struct sigaction */
#define sa_handler 0 /* in union with sa_sigaction */
#define sa_mask 4
#define sa_flags 8
#define sa_restorer 12
/* offsets from stack pointer */
#define mynewact 16 /* struct sigaction */
#define myoldact 32
#define newmask 64 /* signal set */
#define oldmask 68
#define oldhandler 72
#define myret 76
#define savelr 80
#define signum 84 /* first argument */
#define newact 88
#define oldact 92
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
.sect .text; .sect .rodata; .sect .data; .sect .bss
/*
* Linux calls signal handlers with arguments in registers, but the
* ACK expects arguments on the stack. This sigaction() uses a
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
* "bridge" to move the arguments, but
*
* - If the caller passes a bad pointer, this sigaction() causes
* SIGBUS or SIGSEGV instead of setting errno = EFAULT.
*
* - This sigaction() only works with signals 1 to 31, not with
* real-time signals 32 to 64.
*
* - This sigaction() is not safe for multiple threads.
*
* int sigaction(int signum, const struct sigaction *newact,
* struct sigaction *oldact);
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
*/
.sect .text
.define _sigaction
_sigaction:
mflr r0
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
li r3, __NR_sigprocmask
stwu r3, -signum(sp) /* keep 0(sp) = __NR_sigprocmask */
stw r0, savelr(sp)
/* Copy newact to stack (before blocking SIGBUS, SIGSEGV). */
lwz r3, newact(sp)
mr. r3, r3
beq 1f /* skip if newact == NULL */
lwz r4, sa_handler(r3)
lwz r5, sa_mask(r3)
lwz r6, sa_flags(r3)
lwz r7, sa_restorer(r3)
stw r4, mynewact+sa_handler(sp)
stw r5, mynewact+sa_mask(sp)
stw r6, mynewact+sa_flags(sp)
stw r7, mynewact+sa_restorer(sp)
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
/*
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
* Block all signals to prevent a race. After we set sharray,
* we must call the kernel's sigaction before the next signal
* handler runs. This prevents two problems:
*
* - The bridge might call the new handler while the kernel
* uses the mask and flags of the old handler.
*
* - The signal handler might call sigaction() and destroy
* sharray. We must block all signals because any signal
* handler might call sigaction() for our signal.
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
*/
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
1: li r4, SIG_SETMASK
li r5, -1 /* mask signals 1 to 32 */
stw r5, newmask(sp)
la r5, newmask(sp)
la r6, oldmask(sp)
stw r4, 4(sp) /* kept 0(sp) = __NR_sigprocmask */
stw r5, 8(sp)
stw r6, 12(sp)
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
bl __syscall
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
/*
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
* If the signal number is in range 1 to 31, and the new
* handler is not SIG_DFL 0 or SIG_IGN 1, then we interpose
* our bridge.
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
*/
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
lwz r4, signum(sp) /* keep r4 = signum */
addi r5, r4, -1
cmplwi r5, 30
bgt 2f /* skip if out of range */
slwi r5, r5, 2 /* r5 = sharray index */
lis r6, ha16[sharray]
la r6, lo16[sharray](r6) /* r6 = sharray */
lwzx r0, r6, r5
stw r0, oldhandler(sp) /* remember old handler */
lwz r0, newact(sp)
mr. r0, r0
beq 2f /* skip if newact == NULL */
lwz r3, mynewact+sa_handler(sp)
cmplwi r3, 2 /* r3 = new handler */
blt 2f /* skip if SIG_DFL or SIG_IGN */
stwx r3, r6, r5 /* put new handler in sharray */
lis r3, ha16[sigbridge]
la r3, lo16[sigbridge](r3)
stw r3, mynewact+sa_handler(sp)
/* Call the kernel's sigaction. */
/* sigaction(signum, &mynewact or NULL, &myoldact or NULL) */
2: li r3, __NR_sigaction
lwz r0, newact(sp)
mr. r0, r0
beq 3f
la r5, mynewact(sp)
b 4f
3: li r5, 0
4: lwz r0, oldact(sp)
mr. r0, r0
beq 5f
la r6, myoldact(sp)
b 6f
5: li r6, 0
6: stw r3, 0(sp)
stw r4, 4(sp) /* kept r4 = signum */
stw r5, 8(sp)
stw r6, 12(sp)
bl __syscall
stw r3, myret(sp)
/* Unblock signals by restoring old signal mask. */
li r3, __NR_sigprocmask
li r4, SIG_SETMASK
la r5, oldmask(sp)
li r6, 0
stw r3, 0(sp)
stw r4, 4(sp)
stw r5, 8(sp)
stw r6, 12(sp)
bl __syscall
/* Copy oldact from stack (after unblocking BUS, SEGV). */
lwz r3, oldact(sp)
mr. r3, r3
beq 8f /* skip if oldact == NULL */
lwz r4, myoldact+sa_handler(sp)
lis r5, ha16[sigbridge]
la r5, lo16[sigbridge](r5)
cmpw r4, r5
bne 7f
lwz r4, oldhandler(sp)
7: lwz r5, myoldact+sa_mask(sp)
lwz r6, myoldact+sa_flags(sp)
lwz r7, myoldact+sa_restorer(sp)
stw r4, sa_handler(r3)
stw r5, sa_mask(r3)
stw r6, sa_flags(r3)
stw r7, sa_restorer(r3)
8: lwz r0, savelr(sp)
lwz r3, myret(sp)
addi sp, sp, signum
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
mtlr r0
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
blr
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
/*
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
* Linux calls sigbridge(signum) or sigbridge(signum, info, context)
* with arguments in registers r3, r4, r5.
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
*/
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
sigbridge:
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
mflr r0
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
stwu r3, -16(sp) /* signal number */
stw r4, 4(sp) /* info */
stw r5, 8(sp) /* context */
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
stw r0, 12(r1)
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
lis r6, hi16[sharray - 4]
la r6, lo16[sharray - 4](r6)
slwi r7, r3, 2
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
lwzx r6, r6, r7
mtctr r6
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
bctrl /* call our signal handler */
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
lwz r0, 12(sp)
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
addi r1, r1, 16
mtlr r0
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
blr /* sigreturn(2) */
Fix parameters of signal handlers for linuxppc. Linux passes the arguments in registers, but our compiler expects arguments on the stack. Signal handlers got garbage instead of the signal number. Some handlers, like the one in lang/m2/libm2/sigtrp.c, need the correct signal number. I write a "bridge" in PowerPC assembly that moves the arguments to the stack. I put the bridge in sigaction(), so I provide a signal() that calls sigaction(). I remove the *.c glob or wildcard from build.lua, so linuxppc only compiles its own signal.c, not the other signal.c for linux386 and linux68k. My bridge uses sigprocmask(), so I also add sigprocmask(). Because linux386 and linux68k use globs, they also get sigprocmask(). I sync the header files so all three Linux platforms declare execve(), sigprocmask(), and unlink(), but not remove(), because we have remove() in <stdio.h>. I am using sigaction.s to test some features that we recently added to our PowerPC assembler. These are the "hi16[...]" and "lo16[...]" syntax, and also the extended names like "beq", "cmpwi", "li", "subi".
2017-01-22 05:52:32 +00:00
.sect .bss
Rewrite sigaction() to prevent another race. A signal handler might call sigaction(). We must block all signals, not only our signal, to prevent a race between us and the next signal handler. Use /* comments */ because cpp might expand macros in ! comments though such expansion is probably harmless. The bridge is now shorter by 2 instructions.
2018-01-11 22:59:02 +00:00
sharray:
.space 4 * 31 /* handlers for signals 1 to 31 */
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