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