39 lines
		
	
	
	
		
			605 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			39 lines
		
	
	
	
		
			605 B
		
	
	
	
		
			C
		
	
	
	
	
	
| /* $Source$
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|  * $State$
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|  * $Revision$
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|  */
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| 
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| #include <stdlib.h>
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| #include <unistd.h>
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| #include <errno.h>
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| #include "libsys.h"
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| 
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| #define	OUT_OF_MEMORY (void*)(-1)	/* sbrk returns this on failure */
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| 
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| static char* current = NULL;
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|  
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| void* sbrk(intptr_t increment)
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| {
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| 	char* old;
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| 	char* new;
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| 	char* actual;
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| 	
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| 	if (!current)
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| 		current = (char*) _syscall(__NR_brk, 0, 0, 0);
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| 
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| 	if (increment == 0)
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| 		return current;
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| 		
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| 	old = current;
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| 	new = old + increment;
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| 
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| 	actual = (char*) _syscall(__NR_brk, (quad) new, 0, 0);
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| 	if (actual < new)
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| 	{
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| 		errno = ENOMEM;
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| 		return OUT_OF_MEMORY;
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| 	}
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| 		
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| 	current = actual;
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| 	return old;
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| }
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