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authorkolya <kolya>2008-08-22 00:26:22 +0000
committerkolya <kolya>2008-08-22 00:26:22 +0000
commit02cc595f28f10067dcaacc7e147a3db7da277244 (patch)
treed743b6b39af5ad7268a69b3fa3bc4e78ac2fe191
parent5c5470a2fa608204326c6eb06647037532a14655 (diff)
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clean up circular buffers, so pipe can queue 512 bytes rather than 511
-rw-r--r--console.c14
-rw-r--r--pipe.c12
2 files changed, 12 insertions, 14 deletions
diff --git a/console.c b/console.c
index 5e5f034..8681540 100644
--- a/console.c
+++ b/console.c
@@ -186,9 +186,9 @@ console_write(struct inode *ip, char *buf, int n)
struct {
struct spinlock lock;
char buf[INPUT_BUF];
- int r; // Read index
- int w; // Write index
- int e; // Edit index
+ uint r; // Read index
+ uint w; // Write index
+ uint e; // Edit index
} input;
#define C(x) ((x)-'@') // Control-x
@@ -205,20 +205,20 @@ console_intr(int (*getc)(void))
procdump();
break;
case C('U'): // Kill line.
- while(input.e > input.w &&
+ while(input.e != input.w &&
input.buf[(input.e-1) % INPUT_BUF] != '\n'){
input.e--;
cons_putc(BACKSPACE);
}
break;
case C('H'): // Backspace
- if(input.e > input.w){
+ if(input.e != input.w){
input.e--;
cons_putc(BACKSPACE);
}
break;
default:
- if(c != 0 && input.e < input.r+INPUT_BUF){
+ if(c != 0 && input.e-input.r < INPUT_BUF){
input.buf[input.e++ % INPUT_BUF] = c;
cons_putc(c);
if(c == '\n' || c == C('D') || input.e == input.r+INPUT_BUF){
@@ -293,7 +293,7 @@ panic(char *s)
__asm __volatile("cli");
use_console_lock = 0;
cprintf("cpu%d: panic: ", cpu());
- cprintf(s, 0);
+ cprintf(s);
cprintf("\n");
getcallerpcs(&s, pcs);
for(i=0; i<10; i++)
diff --git a/pipe.c b/pipe.c
index 43f623a..fda3788 100644
--- a/pipe.c
+++ b/pipe.c
@@ -11,8 +11,8 @@
struct pipe {
int readopen; // read fd is still open
int writeopen; // write fd is still open
- int writep; // next index to write
- int readp; // next index to read
+ uint writep; // next index to write
+ uint readp; // next index to read
struct spinlock lock;
char data[PIPESIZE];
};
@@ -83,7 +83,7 @@ pipewrite(struct pipe *p, char *addr, int n)
acquire(&p->lock);
for(i = 0; i < n; i++){
- while(((p->writep + 1) % PIPESIZE) == p->readp){
+ while(p->writep == p->readp + PIPESIZE) {
if(p->readopen == 0 || cp->killed){
release(&p->lock);
return -1;
@@ -91,8 +91,7 @@ pipewrite(struct pipe *p, char *addr, int n)
wakeup(&p->readp);
sleep(&p->writep, &p->lock);
}
- p->data[p->writep] = addr[i];
- p->writep = (p->writep + 1) % PIPESIZE;
+ p->data[p->writep++ % PIPESIZE] = addr[i];
}
wakeup(&p->readp);
release(&p->lock);
@@ -115,8 +114,7 @@ piperead(struct pipe *p, char *addr, int n)
for(i = 0; i < n; i++){
if(p->readp == p->writep)
break;
- addr[i] = p->data[p->readp];
- p->readp = (p->readp + 1) % PIPESIZE;
+ addr[i] = p->data[p->readp++ % PIPESIZE];
}
wakeup(&p->writep);
release(&p->lock);