diff options
| -rw-r--r-- | include/semihosting/softmmu-uaccess.h | 3 | ||||
| -rw-r--r-- | semihosting/uaccess.c | 49 |
2 files changed, 52 insertions, 0 deletions
diff --git a/include/semihosting/softmmu-uaccess.h b/include/semihosting/softmmu-uaccess.h index 0330037..4f08dfc 100644 --- a/include/semihosting/softmmu-uaccess.h +++ b/include/semihosting/softmmu-uaccess.h @@ -53,4 +53,7 @@ void softmmu_unlock_user(CPUArchState *env, void *p, target_ulong addr, target_ulong len); #define unlock_user(s, args, len) softmmu_unlock_user(env, s, args, len) +ssize_t softmmu_strlen_user(CPUArchState *env, target_ulong addr); +#define target_strlen(p) softmmu_strlen_user(env, p) + #endif /* SEMIHOSTING_SOFTMMU_UACCESS_H */ diff --git a/semihosting/uaccess.c b/semihosting/uaccess.c index 0d3b32b..d6997e3 100644 --- a/semihosting/uaccess.c +++ b/semihosting/uaccess.c @@ -8,6 +8,7 @@ */ #include "qemu/osdep.h" +#include "exec/exec-all.h" #include "semihosting/softmmu-uaccess.h" void *softmmu_lock_user(CPUArchState *env, target_ulong addr, @@ -23,6 +24,54 @@ void *softmmu_lock_user(CPUArchState *env, target_ulong addr, return p; } +ssize_t softmmu_strlen_user(CPUArchState *env, target_ulong addr) +{ + int mmu_idx = cpu_mmu_index(env, false); + size_t len = 0; + + while (1) { + size_t left_in_page; + int flags; + void *h; + + /* Find the number of bytes remaining in the page. */ + left_in_page = TARGET_PAGE_SIZE - (addr & ~TARGET_PAGE_MASK); + + flags = probe_access_flags(env, addr, MMU_DATA_LOAD, + mmu_idx, true, &h, 0); + if (flags & TLB_INVALID_MASK) { + return -1; + } + if (flags & TLB_MMIO) { + do { + uint8_t c; + if (cpu_memory_rw_debug(env_cpu(env), addr, &c, 1, 0)) { + return -1; + } + if (c == 0) { + return len; + } + addr++; + len++; + if (len > INT32_MAX) { + return -1; + } + } while (--left_in_page != 0); + } else { + char *p = memchr(h, 0, left_in_page); + if (p) { + len += p - (char *)h; + return len <= INT32_MAX ? (ssize_t)len : -1; + } + addr += left_in_page; + len += left_in_page; + if (len > INT32_MAX) { + return -1; + } + } + } +} + char *softmmu_lock_user_string(CPUArchState *env, target_ulong addr) { /* TODO: Make this something that isn't fixed size. */ |