From 84778508d7403cd32fb4527550738f19aa7b1aa5 Mon Sep 17 00:00:00 2001 From: blueswir1 Date: Sun, 26 Oct 2008 20:33:16 +0000 Subject: Preliminary BSD user emulator support git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5544 c046a42c-6fe2-441c-8c8c-71466251a162 --- bsd-user/uaccess.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) create mode 100644 bsd-user/uaccess.c (limited to 'bsd-user/uaccess.c') diff --git a/bsd-user/uaccess.c b/bsd-user/uaccess.c new file mode 100644 index 0000000000..cc51449b47 --- /dev/null +++ b/bsd-user/uaccess.c @@ -0,0 +1,76 @@ +/* User memory access */ +#include +#include + +#include "qemu.h" + +/* copy_from_user() and copy_to_user() are usually used to copy data + * buffers between the target and host. These internally perform + * locking/unlocking of the memory. + */ +abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len) +{ + abi_long ret = 0; + void *ghptr; + + if ((ghptr = lock_user(VERIFY_READ, gaddr, len, 1))) { + memcpy(hptr, ghptr, len); + unlock_user(ghptr, gaddr, 0); + } else + ret = -TARGET_EFAULT; + + return ret; +} + + +abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len) +{ + abi_long ret = 0; + void *ghptr; + + if ((ghptr = lock_user(VERIFY_WRITE, gaddr, len, 0))) { + memcpy(ghptr, hptr, len); + unlock_user(ghptr, gaddr, len); + } else + ret = -TARGET_EFAULT; + + return ret; +} + +/* XXX: use host strnlen if available ? */ +static int qemu_strnlen(const char *s, int max_len) +{ + int i; + for(i = 0; i < max_len; i++) { + if (s[i] == '\0') + break; + } + return i; +} + +/* Return the length of a string in target memory or -TARGET_EFAULT if + access error */ +abi_long target_strlen(abi_ulong guest_addr1) +{ + uint8_t *ptr; + abi_ulong guest_addr; + int max_len, len; + + guest_addr = guest_addr1; + for(;;) { + max_len = TARGET_PAGE_SIZE - (guest_addr & ~TARGET_PAGE_MASK); + ptr = lock_user(VERIFY_READ, guest_addr, max_len, 1); + if (!ptr) + return -TARGET_EFAULT; + len = qemu_strnlen(ptr, max_len); + unlock_user(ptr, guest_addr, 0); + guest_addr += len; + /* we don't allow wrapping or integer overflow */ + if (guest_addr == 0 || + (guest_addr - guest_addr1) > 0x7fffffff) + return -TARGET_EFAULT; + if (len != max_len) + break; + } + return guest_addr - guest_addr1; +} -- cgit v1.2.1