target/arm/arm-semi: Factor out implementation of SYS_SEEK

Factor out the implementation of SYS_SEEK via the new function
tables.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190916141544.17540-12-peter.maydell@linaro.org

1 files changed, 22 insertions, 9 deletions

diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c
index ecd5133..b5e1d73 100644
--- a/target/arm/arm-semi.c
+++ b/target/arm/arm-semi.c
@@ -389,6 +389,8 @@ typedef uint32_t sys_writefn(ARMCPU *cpu, GuestFD *gf,
 typedef uint32_t sys_readfn(ARMCPU *cpu, GuestFD *gf,
                             target_ulong buf, uint32_t len);
 typedef uint32_t sys_isattyfn(ARMCPU *cpu, GuestFD *gf);
+typedef uint32_t sys_seekfn(ARMCPU *cpu, GuestFD *gf,
+                            target_ulong offset);
 
 static uint32_t host_closefn(ARMCPU *cpu, GuestFD *gf)
 {
@@ -442,6 +444,16 @@ static uint32_t host_isattyfn(ARMCPU *cpu, GuestFD *gf)
     return isatty(gf->hostfd);
 }
 
+static uint32_t host_seekfn(ARMCPU *cpu, GuestFD *gf, target_ulong offset)
+{
+    CPUARMState *env = &cpu->env;
+    uint32_t ret = set_swi_errno(env, lseek(gf->hostfd, offset, SEEK_SET));
+    if (ret == (uint32_t)-1) {
+        return -1;
+    }
+    return 0;
+}
+
 static uint32_t gdb_closefn(ARMCPU *cpu, GuestFD *gf)
 {
     return arm_gdb_syscall(cpu, arm_semi_cb, "close,%x", gf->hostfd);
@@ -468,11 +480,18 @@ static uint32_t gdb_isattyfn(ARMCPU *cpu, GuestFD *gf)
     return arm_gdb_syscall(cpu, arm_semi_cb, "isatty,%x", gf->hostfd);
 }
 
+static uint32_t gdb_seekfn(ARMCPU *cpu, GuestFD *gf, target_ulong offset)
+{
+    return arm_gdb_syscall(cpu, arm_semi_cb, "lseek,%x,%x,0",
+                           gf->hostfd, offset);
+}
+
 typedef struct GuestFDFunctions {
     sys_closefn *closefn;
     sys_writefn *writefn;
     sys_readfn *readfn;
     sys_isattyfn *isattyfn;
+    sys_seekfn *seekfn;
 } GuestFDFunctions;
 
 static const GuestFDFunctions guestfd_fns[] = {
@@ -481,12 +500,14 @@ static const GuestFDFunctions guestfd_fns[] = {
         .writefn = host_writefn,
         .readfn = host_readfn,
         .isattyfn = host_isattyfn,
+        .seekfn = host_seekfn,
     },
     [GuestFDGDB] = {
         .closefn = gdb_closefn,
         .writefn = gdb_writefn,
         .readfn = gdb_readfn,
         .isattyfn = gdb_isattyfn,
+        .seekfn = gdb_seekfn,
     },
 };
 
@@ -656,15 +677,7 @@ target_ulong do_arm_semihosting(CPUARMState *env)
             return set_swi_errno(env, -1);
         }
 
-        if (use_gdb_syscalls()) {
-            return arm_gdb_syscall(cpu, arm_semi_cb, "lseek,%x,%x,0",
-                                   gf->hostfd, arg1);
-        } else {
-            ret = set_swi_errno(env, lseek(gf->hostfd, arg1, SEEK_SET));
-            if (ret == (uint32_t)-1)
-              return -1;
-            return 0;
-        }
+        return guestfd_fns[gf->type].seekfn(cpu, gf, arg1);
     case TARGET_SYS_FLEN:
         GET_ARG(0);