New elegant I/O blocking solution

This is done using an internal scheduler syscall (127).

Very nice!

2 files changed, 6 insertions, 4 deletions

diff --git a/libs/libc/inc/sys.h b/libs/libc/inc/sys.h
index ee82946..749888a 100644
--- a/libs/libc/inc/sys.h
+++ b/libs/libc/inc/sys.h
@@ -81,10 +81,12 @@ res read(const char *path, void *buf, u32 offset, u32 count) NONNULL;
 res write(const char *path, const void *buf, u32 offset, u32 count) NONNULL;
 res stat(const char *path, struct stat *buf) NONNULL;
 res exec(const char *path, ...) ATTR((nonnull(1))) SENTINEL;
-res io_poll(u32 *devs);
-res io_read(enum io_type io, void *buf, u32 offset, u32 count);
-res io_write(enum io_type io, void *buf, u32 offset, u32 count);
+
+res io_poll(u32 *devs) NONNULL;
+res io_read(enum io_type io, void *buf, u32 offset, u32 count) NONNULL;
+res io_write(enum io_type io, void *buf, u32 offset, u32 count) NONNULL;
 res io_control(enum io_type io, ...);
+
 res yield(void);
 res boot(u32 cmd);
 
diff --git a/libs/libc/print.c b/libs/libc/print.c
index 425eb01..27048bd 100644
--- a/libs/libc/print.c
+++ b/libs/libc/print.c
@@ -233,7 +233,7 @@ void print_trace(u32 count)
 	} * stk;
 	__asm__ volatile("movl %%ebp, %0;" : "=r"(stk));
 	print("EBP\tEIP\n");
-	for (u32 i = 0; stk && i < count; i++) {
+	for (u32 i = 0; stk && memory_readable(stk) && i < count; i++) {
 		printf("0x%x\t0x%x\n", stk->ebp, stk->eip);
 		stk = stk->ebp;
 	}