/* When we enter this piece of code, the program stack looks like this: argc argument counter (integer) argv[0] program name (pointer) argv[1...N] program args (pointers) argv[argc-1] end of args (integer) NULL env[0...N] environment variables (pointers) NULL */ #include #include .text .global __start .type __start,%function .type __uClibc_start_main,%function .weak _init .weak _fini .type __uClibc_start_main,%function /* Stick in a dummy reference to main(), so that if an application * is linking when the main() function is in a static library (.a) * we can be sure that main() actually gets linked in */ .type main,%function __start: #ifdef __PIC__ .set noreorder bltzal zero,0f nop 0: .cpload $31 .set reorder #endif move $31, zero /* no return, but since the jal kills $31, skip this */ lw a0, 0($29) /* argc */ addu a1, $29, 4 /* get to start of argv */ addu a2, a0, 1 /* argv[0] program name (ordinal->cardinal) */ sll a2, a2, 2 /* multiple by 4 */ add a2, a2, a1 /* a2 now points to start of envp */ la a3, _init /* a3 is address of _init */ addiu sp, sp, -24 /* 16 + 4 rounded up to multiple of 8 */ /* multiple of 8 for longlong/double support */ la v0, _fini sw v0, 16(sp) /* stack has 5th argument, address of _fini */ /* Ok, now run uClibc's main() -- shouldn't return */ jal __uClibc_start_main addiu sp, sp, 24 /* undo stack argument */ /* Crash if somehow `exit' returns anyways. */ hlt: b hlt /* Define a symbol for the first piece of initialized data. */ .data .globl __data_start __data_start: .long 0 .weak data_start data_start = __data_start
