C - accessing parameter inside the function - c

Question

I have a main.c file
int boyut(const char* string);
char greeting[6] = {"Helle"};
int main(){
greeting[5] = 0x00;
int a = boyut(greeting);
return 0;
}
int boyut(const char* string){
int len=0;
while(string[len]){
len++;
}
return len;
}
I compile it with GCC command gcc -Wall -m32 -nostdlib main.c -o main.o
When I check disassembly, I see the variable greeting is placed in .data segment. And before calling boyut it's not pushed into stack. Inside the boyut function, it acts like variable greeting is in stack segment. So that variable actually not being accessed inside the function. Why is it generating a code like this? How can I correct this?
Disassembly of section .text:
080480f8 <main>:
80480f8: 55 push ebp
80480f9: 89 e5 mov ebp,esp
80480fb: 83 ec 18 sub esp,0x18
80480fe: c6 05 05 a0 04 08 00 mov BYTE PTR ds:0x804a005,0x0
8048105: 83 ec 0c sub esp,0xc
8048108: 68 00 a0 04 08 push 0x804a000
804810d: e8 0d 00 00 00 call 804811f <boyut>
8048112: 83 c4 10 add esp,0x10
8048115: 89 45 f4 mov DWORD PTR [ebp-0xc],eax
8048118: b8 00 00 00 00 mov eax,0x0
804811d: c9 leave
804811e: c3 ret
0804811f <boyut>:
804811f: 55 push ebp
8048120: 89 e5 mov ebp,esp
8048122: 83 ec 10 sub esp,0x10
8048125: c7 45 fc 00 00 00 00 mov DWORD PTR [ebp-0x4],0x0
804812c: eb 04 jmp 8048132 <boyut+0x13>
804812e: 83 45 fc 01 add DWORD PTR [ebp-0x4],0x1
8048132: 8b 55 fc mov edx,DWORD PTR [ebp-0x4]
8048135: 8b 45 08 mov eax,DWORD PTR [ebp+0x8]
8048138: 01 d0 add eax,edx
804813a: 0f b6 00 movzx eax,BYTE PTR [eax]
804813d: 84 c0 test al,al
804813f: 75 ed jne 804812e <boyut+0xf>
8048141: 8b 45 fc mov eax,DWORD PTR [ebp-0x4]
8048144: c9 leave
8048145: c3 ret
main.o: file format elf32-i386
Contents of section .data:
804a000 48656c6c 6500 Helle.

Answer 1

The function boyut is declared like this:
int boyut(const char* string);
That means: boyut takes a pointer to char and returns an int. And indeed, the compiler pushes a point to char on the stack. This pointer points to the beginning of greeting. This happens, because in C, an array is implicitly converted to a pointer to its first element under most circumstances.
If you want to pass an array to a function so it is copied to the function, you have to wrap the array into a structure and pass that.