49 lines
1.2 KiB
C
49 lines
1.2 KiB
C
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/*
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Simple Executable Code Format
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SECF is a executable format for any platform (though designed with x86(-32) in mind.)
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that makes use of registers, syscalls/interrupts, and other tables/structures instead of libraries.
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register map:
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(unused means the program can use the register without any issue, no data used/passed by the SECF will be there)
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EAX: unused
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EBX: unused
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ECX: arg string length
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EDX: variable area size (bytes)
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ESI: pointer to arg string
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EDI: unused
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ESP: unused, normal function
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EBP: pointer to variable area
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The variable area is a area of a specific size (size in EDX) that can be used for storing variables/temporary data.
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Any additional memory space needed can be aquired via malloc.
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The minimum size of the variable area is 16 bytes and a maximum size of 64KiB.
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Use syscall/int (number TBT) to call functions
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*/
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#include <types.h>
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#include <stdlib.h>
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void* init_var_area(size_t size)
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{
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if (size == (size_t) 0)
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{
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return NULL; /* size 0 is invalid. */
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}
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else if (size >= 65536)
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{
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return NULL; /* size above 65,536 is invalid. */
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}
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else if (size < 16)
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{
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size = 16;
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}
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return malloc(size); /* No need to check for null because we'd return null in that case */
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}
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