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Diffstat (limited to 'libc/sysdeps/linux/i386/sbrk.c')
-rw-r--r--libc/sysdeps/linux/i386/sbrk.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/i386/sbrk.c b/libc/sysdeps/linux/i386/sbrk.c
new file mode 100644
index 000000000..f5099d7e8
--- /dev/null
+++ b/libc/sysdeps/linux/i386/sbrk.c
@@ -0,0 +1,35 @@
+/* From libc-5.3.12 */
+
+#include <unistd.h>
+#include <sys/syscall.h>
+#include <errno.h>
+
+extern void * ___brk_addr;
+
+extern int __init_brk (void);
+
+void *
+sbrk(ptrdiff_t increment)
+{
+ if (__init_brk () == 0)
+ {
+ void * tmp = ___brk_addr+increment;
+#if defined(__PIC__) || defined (__pic__)
+ __asm__ volatile ("pushl %%ebx\n\t"
+ "movl %%ecx,%%ebx\n\t"
+ "int $0x80\n\t"
+ "popl %%ebx"
+ :"=a" (___brk_addr)
+ :"0" (SYS_brk),"c" (tmp));
+#else
+ __asm__ volatile ("int $0x80"
+ :"=a" (___brk_addr)
+ :"0" (SYS_brk),"b" (tmp));
+#endif
+ if (___brk_addr == tmp)
+ return tmp-increment;
+ errno = ENOMEM;
+ return ((void *) -1);
+ }
+ return ((void *) -1);
+}