1 #include "buffer.h" |
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2 #include "logging.h" |
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3 |
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4 #include <stdlib.h> |
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5 #include <limits.h> |
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6 #include <string.h> |
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7 |
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8 typedef struct _flib_vector { |
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9 void *data; |
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10 size_t size; |
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11 size_t capacity; |
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12 } _flib_vector; |
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13 |
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14 flib_vector flib_vector_create() { |
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15 flib_vector result = malloc(sizeof(_flib_vector)); |
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16 if(result == NULL) { |
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17 return NULL; |
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18 } |
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19 result->data = malloc(16); |
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20 if(result->data == NULL) { |
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21 free(result); |
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22 return NULL; |
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23 } |
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24 result->size = 0; |
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25 result->capacity = 16; |
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26 return result; |
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27 } |
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28 |
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29 void flib_vector_destroy(flib_vector *vec) { |
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30 if(vec && *vec) { |
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31 free((*vec)->data); |
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32 free(*vec); |
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33 *vec = NULL; |
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34 } |
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35 } |
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36 |
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37 static void try_realloc(flib_vector vec, size_t newCapacity) { |
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38 void *newData = realloc(vec->data, newCapacity); |
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39 if(newData) { |
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40 vec->data = newData; |
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41 vec->capacity = newCapacity; |
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42 } |
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43 } |
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44 |
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45 static size_t getFreeCapacity(flib_vector vec) { |
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46 return vec->capacity - vec->size; |
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47 } |
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48 |
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49 int flib_vector_append(flib_vector vec, const void *data, size_t len) { |
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50 if(getFreeCapacity(vec) < len) { |
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51 // Resize exponentially for constant amortized time, |
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52 // But at least by as much as we need of course, |
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53 // and be extra careful with integer overflows... |
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54 size_t extraCapacity = (vec->capacity)/2; |
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55 |
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56 size_t minExtraCapacity = len - getFreeCapacity(vec); |
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57 if(extraCapacity < minExtraCapacity) { |
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58 extraCapacity = minExtraCapacity; |
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59 } |
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60 |
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61 if(extraCapacity <= SIZE_MAX - vec->capacity) { |
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62 try_realloc(vec, vec->capacity+extraCapacity); |
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63 } |
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64 |
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65 // Check if we were able to resize. |
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66 // If not, try to allocate at least what we need... |
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67 if(getFreeCapacity(vec) < len) { |
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68 try_realloc(vec, vec->capacity+minExtraCapacity); |
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69 |
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70 // Still not working? Then we fail. |
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71 if(getFreeCapacity(vec) < len) { |
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72 return 0; |
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73 } |
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74 } |
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75 } |
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76 |
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77 memmove(vec->data + vec->size, data, len); |
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78 vec->size += len; |
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79 return len; |
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80 } |
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81 |
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82 flib_buffer flib_vector_as_buffer(flib_vector vec) { |
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83 flib_buffer result = {vec->data, vec->size}; |
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84 return result; |
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85 } |
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86 |
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87 flib_constbuffer flib_vector_as_constbuffer(flib_vector vec) { |
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88 flib_constbuffer result = {vec->data, vec->size}; |
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89 return result; |
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90 } |
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