command: Add command_decode_ptr() helper

Add a helper function to convert from a string buffer passed in the
args[] parameter to an actual pointer.  This avoids all the callers
needing to perfrom pointer manipulation.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 12 insertions, 16 deletions

diff --git a/src/i2ccmds.c b/src/i2ccmds.c
index 388af6ed..cde0f6fa 100644
--- a/src/i2ccmds.c
+++ b/src/i2ccmds.c
@@ -4,6 +4,7 @@
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
+#include <string.h> // memcpy
 #include "basecmd.h" //oid_alloc
 #include "command.h"  //sendf
 #include "sched.h" //DECL_COMMAND
@@ -30,7 +31,7 @@ command_i2c_write(uint32_t *args)
     uint8_t oid = args[0];
     struct i2cdev_s *i2c = oid_lookup(oid, command_config_i2c);
     uint8_t data_len = args[1];
-    uint8_t *data = (void*)(size_t)args[2];
+    uint8_t *data = command_decode_ptr(args[2]);
     i2c_write(i2c->i2c_config, data_len, data);
 }
 DECL_COMMAND(command_i2c_write, "i2c_write oid=%c data=%*s");
@@ -41,10 +42,9 @@ command_i2c_read(uint32_t * args)
     uint8_t oid = args[0];
     struct i2cdev_s *i2c = oid_lookup(oid, command_config_i2c);
     uint8_t reg_len = args[1];
-    uint8_t *reg = (void*)(size_t)args[2];
+    uint8_t *reg = command_decode_ptr(args[2]);
     uint8_t data_len = args[3];
-    uint8_t receive_array[data_len];
-    uint8_t *data = (void*)(size_t)receive_array;
+    uint8_t data[data_len];
     i2c_read(i2c->i2c_config, reg_len, reg, data_len, data);
     sendf("i2c_read_response oid=%c response=%*s", oid, data_len, data);
 }
@@ -56,24 +56,20 @@ command_i2c_modify_bits(uint32_t *args)
     uint8_t oid = args[0];
     struct i2cdev_s *i2c = oid_lookup(oid, command_config_i2c);
     uint8_t reg_len = args[1];
-    uint8_t *reg = (void*)(size_t)args[2];
+    uint8_t *reg = command_decode_ptr(args[2]);
     uint32_t clear_set_len = args[3];
-    if (clear_set_len % 2 != 0) {
+    if (clear_set_len % 2 != 0)
         shutdown("i2c_modify_bits: Odd number of bits!");
-    }
     uint8_t data_len = clear_set_len/2;
-    uint8_t *clear_set = (void*)(size_t)args[4];
-    uint8_t receive_array[reg_len + data_len];
-    uint8_t *receive_data = (void*)(size_t)receive_array;
-    for (int i = 0; i < reg_len; i++) {
-        *(receive_data + i) = *(reg + i);
-    }
+    uint8_t *clear_set = command_decode_ptr(args[4]);
+    uint8_t receive_data[reg_len + data_len];
+    memcpy(receive_data, reg, reg_len);
     i2c_read(i2c->i2c_config, reg_len, reg, data_len, receive_data + reg_len);
     for (int i = 0; i < data_len; i++) {
-        *(receive_data + reg_len + i) &= ~(*(clear_set + i));
-        *(receive_data + reg_len + i) |= *(clear_set + clear_set_len/2 + i);
+        receive_data[reg_len + i] &= ~clear_set[i];
+        receive_data[reg_len + i] |= clear_set[data_len + i];
     }
-    i2c_write(i2c->i2c_config, reg_len + data_len, receive_array);
+    i2c_write(i2c->i2c_config, reg_len + data_len, receive_data);
 }
 DECL_COMMAND(command_i2c_modify_bits,
              "i2c_modify_bits oid=%c reg=%*s clear_set_bits=%*s");