projects / lttng-tools.git / blame
| Commit | Line | Data |
|---|---|---|
| 0ae3cfc6 SM |
1 | /* |
| 2 | * Copyright 2020 EfficiOS, Inc. | |
| 3 | * | |
| 4 | * SPDX-License-Identifier: GPL-2.0-only | |
| 5 | * | |
| 6 | */ | |
| 7 | ||
| 8 | #include "bytecode.h" | |
| 9 | ||
| 10 | #include <errno.h> | |
| 11 | ||
| 12 | #include "common/align.h" | |
| 13 | ||
| 14 | #define INIT_ALLOC_SIZE 4 | |
| 15 | ||
| 16 | static inline int get_count_order(unsigned int count) | |
| 17 | { | |
| 18 | int order; | |
| 19 | ||
| 20 | order = lttng_fls(count) - 1; | |
| 21 | if (count & (count - 1)) | |
| 22 | order++; | |
| 23 | return order; | |
| 24 | } | |
| 25 | ||
| 26 | LTTNG_HIDDEN | |
| 27 | int bytecode_init(struct lttng_filter_bytecode_alloc **fb) | |
| 28 | { | |
| 29 | uint32_t alloc_len; | |
| 30 | ||
| 31 | alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + INIT_ALLOC_SIZE; | |
| 32 | *fb = calloc(alloc_len, 1); | |
| 33 | if (!*fb) { | |
| 34 | return -ENOMEM; | |
| 35 | } else { | |
| 36 | (*fb)->alloc_len = alloc_len; | |
| 37 | return 0; | |
| 38 | } | |
| 39 | } | |
| 40 | ||
| 41 | LTTNG_HIDDEN | |
| 42 | int32_t bytecode_reserve(struct lttng_filter_bytecode_alloc **fb, uint32_t align, uint32_t len) | |
| 43 | { | |
| 44 | int32_t ret; | |
| 45 | uint32_t padding = offset_align((*fb)->b.len, align); | |
| 46 | uint32_t new_len = (*fb)->b.len + padding + len; | |
| 47 | uint32_t new_alloc_len = sizeof(struct lttng_filter_bytecode_alloc) + new_len; | |
| 48 | uint32_t old_alloc_len = (*fb)->alloc_len; | |
| 49 | ||
| 50 | if (new_len > LTTNG_FILTER_MAX_LEN) | |
| 51 | return -EINVAL; | |
| 52 | ||
| 53 | if (new_alloc_len > old_alloc_len) { | |
| 54 | struct lttng_filter_bytecode_alloc *newptr; | |
| 55 | ||
| 56 | new_alloc_len = | |
| 57 | max_t(uint32_t, 1U << get_count_order(new_alloc_len), old_alloc_len << 1); | |
| 58 | newptr = realloc(*fb, new_alloc_len); | |
| 59 | if (!newptr) | |
| 60 | return -ENOMEM; | |
| 61 | *fb = newptr; | |
| 62 | /* We zero directly the memory from start of allocation. */ | |
| 63 | memset(&((char *) *fb)[old_alloc_len], 0, new_alloc_len - old_alloc_len); | |
| 64 | (*fb)->alloc_len = new_alloc_len; | |
| 65 | } | |
| 66 | (*fb)->b.len += padding; | |
| 67 | ret = (*fb)->b.len; | |
| 68 | (*fb)->b.len += len; | |
| 69 | return ret; | |
| 70 | } | |
| 71 | ||
| 72 | LTTNG_HIDDEN | |
| 73 | int bytecode_push(struct lttng_filter_bytecode_alloc **fb, const void *data, | |
| 74 | uint32_t align, uint32_t len) | |
| 75 | { | |
| 76 | int32_t offset; | |
| 77 | ||
| 78 | offset = bytecode_reserve(fb, align, len); | |
| 79 | if (offset < 0) | |
| 80 | return offset; | |
| 81 | memcpy(&(*fb)->b.data[offset], data, len); | |
| 82 | return 0; | |
| 83 | } | |
| 84 | ||
| 85 | LTTNG_HIDDEN | |
| 86 | int bytecode_push_logical(struct lttng_filter_bytecode_alloc **fb, | |
| 87 | struct logical_op *data, | |
| 88 | uint32_t align, uint32_t len, | |
| 89 | uint16_t *skip_offset) | |
| 90 | { | |
| 91 | int32_t offset; | |
| 92 | ||
| 93 | offset = bytecode_reserve(fb, align, len); | |
| 94 | if (offset < 0) | |
| 95 | return offset; | |
| 96 | memcpy(&(*fb)->b.data[offset], data, len); | |
| 97 | *skip_offset = | |
| 98 | (void *) &((struct logical_op *) &(*fb)->b.data[offset])->skip_offset | |
| 99 | - (void *) &(*fb)->b.data[0]; | |
| 100 | return 0; | |
| 101 | } |