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believe it or not, this was working

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the macro expansion of "char *cp;" turned into
char *(curproc[cpu()]);  which declares a dynamically
sized array of char* called curproc.

so then &cp == &(curproc[cpu()]) was actually a
stack variable as "expected".  it was one past the
end of the array, but the implicit alloca allocated
more than was necessary.

do not tell me that making cp a #define was a bad idea.
there are worse problems to fix.  more on that later.
This commit is contained in:
rsc 2007-09-27 05:13:10 +00:00
parent 90d975e9c8
commit 666f58c711
3 changed files with 14 additions and 10 deletions
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8
dot-bochsrc
View file

@ -74,7 +74,8 @@
# now supported, but we still recommend to use the BIOS distributed with # now supported, but we still recommend to use the BIOS distributed with
# Bochs. Now the start address can be calculated from image size. # Bochs. Now the start address can be calculated from image size.
#======================================================================= #=======================================================================
romimage: file=$BXSHARE/BIOS-bochs-latest, address=0xf0000 #romimage: file=$BXSHARE/BIOS-bochs-latest
romimage: file=/home/rsc/pub/bochs/bios/BIOS-bochs-latest
#romimage: file=mybios.bin, address=0xfff80000 # 512k at memory top #romimage: file=mybios.bin, address=0xfff80000 # 512k at memory top
#romimage: file=mybios.bin # calculate start address from image size #romimage: file=mybios.bin # calculate start address from image size
@ -107,7 +108,7 @@ romimage: file=$BXSHARE/BIOS-bochs-latest, address=0xf0000
# 650Mhz Athlon K-7 with Linux 2.4.4/egcs-2.91.66 2 to 2.5 Mips # 650Mhz Athlon K-7 with Linux 2.4.4/egcs-2.91.66 2 to 2.5 Mips
# 400Mhz Pentium II with Linux 2.0.36/egcs-1.0.3 1 to 1.8 Mips # 400Mhz Pentium II with Linux 2.0.36/egcs-1.0.3 1 to 1.8 Mips
#======================================================================= #=======================================================================
cpu: count=2, ips=10000000 cpu: count=2, ips=10000000, quantum=1
#======================================================================= #=======================================================================
# MEGS # MEGS
@ -403,7 +404,7 @@ debug: action=ignore
#======================================================================= #=======================================================================
#debugger_log: /dev/null #debugger_log: /dev/null
#debugger_log: debugger.out #debugger_log: debugger.out
debugger_log: - debugger_log: bochsout.txt
#======================================================================= #=======================================================================
# COM1, COM2, COM3, COM4: # COM1, COM2, COM3, COM4:
@ -675,6 +676,7 @@ keyboard_mapping: enabled=0, map=
# i440fxsupport: enabled=1, slot1=pcivga, slot2=ne2k # i440fxsupport: enabled=1, slot1=pcivga, slot2=ne2k
#======================================================================= #=======================================================================
#i440fxsupport: enabled=1 #i440fxsupport: enabled=1
i440fxsupport: enabled=1
#======================================================================= #=======================================================================
# USB1: # USB1:

12
sysfile.c
View file

@ -49,11 +49,11 @@ sys_read(void)
{ {
struct file *f; struct file *f;
int n; int n;
char *cp; char *p;
if(argfd(0, 0, &f) < 0 || argint(2, &n) < 0 || argptr(1, &cp, n) < 0) if(argfd(0, 0, &f) < 0 || argint(2, &n) < 0 || argptr(1, &p, n) < 0)
return -1; return -1;
return fileread(f, cp, n); return fileread(f, p, n);
} }
int int
@ -61,11 +61,11 @@ sys_write(void)
{ {
struct file *f; struct file *f;
int n; int n;
char *cp; char *p;
if(argfd(0, 0, &f) < 0 || argint(2, &n) < 0 || argptr(1, &cp, n) < 0) if(argfd(0, 0, &f) < 0 || argint(2, &n) < 0 || argptr(1, &p, n) < 0)
return -1; return -1;
return filewrite(f, cp, n); return filewrite(f, p, n);
} }
int int

4
usertests.c
View file

@ -1234,7 +1234,9 @@ int
main(int argc, char *argv[]) main(int argc, char *argv[])
{ {
printf(1, "usertests starting\n"); printf(1, "usertests starting\n");
for(;;) concreate();
if(open("usertests.ran", 0) >= 0){ if(open("usertests.ran", 0) >= 0){
printf(1, "already ran user tests -- rebuild fs.img\n"); printf(1, "already ran user tests -- rebuild fs.img\n");
exit(); exit();