Creates an interned Lua string from the data pointed to by ptr.
If the optional argument len is missing, ptr is converted to a “char *” and the data is assumed to be zero-terminated. The length of the string is computed with strlen().
运行以下代码时,我得到了预期的(小端)结果：
ffi = require 'ffi'
ffi.cdef[[
typedef unsigned long uint32_t;
typedef unsigned long long uint64_t;
#pragma pack(1)
struct mystruct
{
uint32_t field1;
char field2[6];
uint64_t field3;
short field4;
};
]]
function string.tohex(str)
return (str:gsub('.', function (c)
return string.format('%02X', string.byte(c))
end))
end
ms = ffi.new('struct mystruct', 1, {2, 3, 4, 5, 6, 7}, 8, 9)
s = ffi.string(ms, ffi.sizeof(ms)) -- specify how long the byte sequence is
print(s:tohex()) --> 01000000020304050607
str = ffi.string(ptr [,len])
Creates an interned Lua string from the data pointed to by ptr.
If the optional argument len is missing, ptr is converted to a "char *" and the data is assumed to be zero-terminated. The length of the string is computed with strlen().
data = ffi.new('struct mystruct') -- create a new cdata
ffi.copy(data, s, ffi.sizeof(data)) -- fill it with data from Lua string 's'
print(data.field1, data.field4) --> 1 9
Creates an interned Lua string from the data pointed to by ptr.
If the optional argument len is missing, ptr is converted to a “char *” and the data is assumed to be zero-terminated. The length of the string is computed with strlen().
运行以下代码时,我得到了预期的(小端)结果：
ffi = require 'ffi'
ffi.cdef[[
typedef unsigned long uint32_t;
typedef unsigned long long uint64_t;
#pragma pack(1)
struct mystruct
{
uint32_t field1;
char field2[6];
uint64_t field3;
short field4;
};
]]
function string.tohex(str)
return (str:gsub('.', function (c)
return string.format('%02X', string.byte(c))
end))
end
ms = ffi.new('struct mystruct', 1, {2, 3, 4, 5, 6, 7}, 8, 9)
s = ffi.string(ms, ffi.sizeof(ms)) -- specify how long the byte sequence is
print(s:tohex()) --> 01000000020304050607
str = ffi.string(ptr [,len])
Creates an interned Lua string from the data pointed to by ptr.
If the optional argument len is missing, ptr is converted to a "char *" and the data is assumed to be zero-terminated. The length of the string is computed with strlen().
data = ffi.new('struct mystruct') -- create a new cdata
ffi.copy(data, s, ffi.sizeof(data)) -- fill it with data from Lua string 's'
print(data.field1, data.field4) --> 1 9
