https://github.com/etchedpixels/centuriontools

Warrex Centurion Tool Chain
https://github.com/etchedpixels/centuriontools

Last synced: 2 months ago
JSON representation

Warrex Centurion Tool Chain

• Host: GitHub
• URL: https://github.com/etchedpixels/centuriontools
• Owner: EtchedPixels
• License: gpl-3.0
• Created: 2022-04-26T19:49:25.000Z (over 2 years ago)
• Default Branch: main
• Last Pushed: 2024-07-11T11:51:07.000Z (7 months ago)
• Last Synced: 2024-07-11T13:21:41.390Z (7 months ago)
• Language: C
• Size: 1.82 MB
• Stars: 4
• Watchers: 4
• Forks: 0
• Open Issues: 1
• Metadata Files:
  • Readme: README.libc
  • License: LICENSE

Awesome Lists containing this project

README

        
Most of the libc code is portable. Some of it ends up slower than we would

like on TMS99xx because there are fancy ways of handling word alignment that

we don't do.

The malloc/free support requires a subset of brk() and sbrk().

sbrk(0) needs to return the address of the base of free memory

brk(n) needs to set the base of free memory to n.

Free memory grows upwards.

A trivial implementation for the TI99/4A with the 0x2000-3FFF area having

the stack at the top and malloc space growing up would be something like

the following (which also implements non zero sbrk semantics correctly)

static unsigned char *mptr = (unsigned char *)0x2000;

void *sbrk(inptr_t n)

{

	unsigned char *p = mptr;

	mptr += n;

	return p;

}

int brk(void *p)

{

	mptr = p;

	return 0;

}

A better implementation might check if it's getting close to the stack and

return -1 (sbrk returns (void *)-1 on error).