Andrew Burgess c5ebe0ff70 sim: Don't overwrite stored errno in sim_syscall_multi ... The host syscall callback mechanism should take care of updating the errcode within the CB_SYSCALL struct, and we should not be adjusting the error code once the syscall has completed. We especially, should not be rewriting the syscall errcode based on the value of errno some time after running the host syscall, as there is no guarantee that errno has not be overwritten. To perform a syscall we call cb_syscall (in syscall.c). To return from cb_syscall control passes through one of two exit paths these are labeled FinishSyscall and ErrorFinish and are reached using goto statements scattered throughout the cb_syscall function. In FinishSyscall we store the syscall result in 'sc->result', and the error code is transated to target encoding, and stored in 'sc->errcode'. In ErrorFinish, we again store the syscall result in 'sc->result', and fill in 'sc->errcode' by fetching the actual errno from the host with the 'cb->get_errno' callback. In both cases 'sc->errcode' will have been filled in with an appropriate value. Further, if we look at a specific syscall example, CB_SYS_open, in this case the first thing we do is fetch the path to open from the target with 'get_path', if this fails then the errcode is returned, and we jump to FinishSyscall. Notice that in this case, no host syscall may have been performed, for example a failure to read the path to open out of simulated memory can return EINVAL without performing any host syscall. Given that no host syscall has been performed, reading the host errno makes absolutely no sense. This commit removes from sim_syscall_multi the rewriting of sc->errcode based on the value of errno, and instead relies on the value stored in the cb_syscall. sim/common/ChangeLog: * sim-syscall.c (sim_syscall_multi): Don't update sc->errcode at this point, it should have already been set in cb_syscall.		2018-12-18 00:02:01 +00:00
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aarch64
arm
avr
bfin
common	sim: Don't overwrite stored errno in sim_syscall_multi	2018-12-18 00:02:01 +00:00
cr16
cris	sim/cris: Fix references to cgen cpu directory	2018-12-06 12:21:11 +00:00
d10v
erc32	[src/erc32] Use ncurses instead of termcap on Cygwin too	2018-10-30 16:41:12 +00:00
frv	sim/opcodes: Allow use of out of tree cgen source directory	2018-12-06 12:21:10 +00:00
ft32
h8300
igen
iq2000	sim/opcodes: Allow use of out of tree cgen source directory	2018-12-06 12:21:10 +00:00
lm32	sim/opcodes: Allow use of out of tree cgen source directory	2018-12-06 12:21:10 +00:00
m32c
m32r	sim/opcodes: Allow use of out of tree cgen source directory	2018-12-06 12:21:10 +00:00
m68hc11
mcore
microblaze
mips
mn10300
moxie
msp430
or1k	sim/opcodes: Allow use of out of tree cgen source directory	2018-12-06 12:21:10 +00:00
ppc
rl78
rx
sh
sh64	sim/opcodes: Allow use of out of tree cgen source directory	2018-12-06 12:21:10 +00:00
testsuite
v850
.gitignore
ChangeLog	sim/opcodes: Allow use of out of tree cgen source directory	2018-12-06 12:21:10 +00:00
configure
configure.ac
configure.tgt
MAINTAINERS
Makefile.in
README-HACKING