1 | /* pseudo system calls for M68HC11 & M68HC12. |
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2 | * Copyright (C) 1999, 2000, 2001, 2002 Stephane Carrez (stcarrez@nerim.fr) |
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3 | * |
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4 | * The authors hereby grant permission to use, copy, modify, distribute, |
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5 | * and license this software and its documentation for any purpose, provided |
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6 | * that existing copyright notices are retained in all copies and that this |
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7 | * notice is included verbatim in any distributions. No written agreement, |
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8 | * license, or royalty fee is required for any of the authorized uses. |
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9 | * Modifications to this software may be copyrighted by their authors |
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10 | * and need not follow the licensing terms described here, provided that |
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11 | * the new terms are clearly indicated on the first page of each file where |
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12 | * they apply. |
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13 | */ |
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14 | |
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15 | #include <sys/types.h> |
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16 | #include <sys/stat.h> |
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17 | #include <unistd.h> |
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18 | |
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19 | extern void outbyte(char c); |
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20 | extern char inbyte(void); |
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21 | |
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22 | int |
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23 | read(int file, void *p, size_t nbytes) |
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24 | { |
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25 | int i = 0; |
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26 | char* buf = (char*) p; |
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27 | |
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28 | for (i = 0; i < nbytes; i++) { |
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29 | *(buf + i) = inbyte(); |
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30 | if ((*(buf + i) == '\n') || (*(buf + i) == '\r')) { |
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31 | i++; |
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32 | break; |
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33 | } |
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34 | } |
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35 | return (i); |
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36 | } |
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37 | |
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38 | int |
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39 | write(int file, const void *p, size_t len) |
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40 | { |
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41 | const char *ptr = (const char*) p; |
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42 | int todo; |
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43 | |
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44 | for (todo = len; todo; --todo) |
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45 | { |
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46 | outbyte (*ptr++); |
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47 | } |
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48 | return(len); |
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49 | } |
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50 | |
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51 | void * |
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52 | sbrk(ptrdiff_t incr) |
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53 | { |
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54 | extern char _end; /* Defined by the linker */ |
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55 | static char *heap_end; |
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56 | char *prev_heap_end; |
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57 | |
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58 | register char *stack_ptr asm ("sp"); |
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59 | |
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60 | if (heap_end == 0) |
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61 | { |
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62 | heap_end = &_end; |
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63 | } |
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64 | prev_heap_end = heap_end; |
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65 | if (heap_end + incr > stack_ptr) |
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66 | { |
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67 | write (1, "Heap and stack collision\n", 25); |
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68 | abort (); |
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69 | } |
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70 | heap_end += incr; |
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71 | return ((void*) prev_heap_end); |
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72 | } |
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73 | |
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74 | /* end of syscalls.c */ |
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