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author | Russ Cox <rsc@swtch.com> | 2020-01-19 22:39:22 -0500 |
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committer | Russ Cox <rsc@swtch.com> | 2020-01-19 23:04:58 -0500 |
commit | 41b3e8b9893a8561af7e85ca98444bc284b4013d (patch) | |
tree | e9bf7fdeefbdb7d2e6c1ebc25c7888b81f0bb16b /src/libthread/386-ucontext.c | |
parent | ac8042dfa9819f76ccfedd4aa36c1239322808b8 (diff) | |
download | plan9port-41b3e8b9893a8561af7e85ca98444bc284b4013d.tar.gz plan9port-41b3e8b9893a8561af7e85ca98444bc284b4013d.tar.bz2 plan9port-41b3e8b9893a8561af7e85ca98444bc284b4013d.zip |
libthread: use consistent stack calculation code in makecontext
Also reduce duplication: makecontext is per-arch not per-os-arch.
May fix #353.
Diffstat (limited to 'src/libthread/386-ucontext.c')
-rw-r--r-- | src/libthread/386-ucontext.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/libthread/386-ucontext.c b/src/libthread/386-ucontext.c new file mode 100644 index 00000000..3afa9513 --- /dev/null +++ b/src/libthread/386-ucontext.c @@ -0,0 +1,22 @@ +#include "threadimpl.h" + +void +makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...) +{ + int *sp; + + sp = USPALIGN(ucp, 4); + sp -= argc; + memmove(sp, &argc+1, argc*sizeof(int)); + *--sp = 0; /* return address */ + ucp->uc_mcontext.mc_eip = (long)func; + ucp->uc_mcontext.mc_esp = (int)sp; +} + +int +swapcontext(ucontext_t *oucp, ucontext_t *ucp) +{ + if(getcontext(oucp) == 0) + setcontext(ucp); + return 0; +} |