epoger@google.com | ec3ed6a | 2011-07-28 14:26:00 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2011 Google Inc. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license that can be |
| 5 | * found in the LICENSE file. |
| 6 | */ |
reed@google.com | 5595af1 | 2012-12-21 15:36:33 +0000 | [diff] [blame] | 7 | |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 8 | #include "SkReader32.h" |
reed@google.com | fd0ffcf | 2011-06-21 15:43:11 +0000 | [diff] [blame] | 9 | #include "SkString.h" |
commit-bot@chromium.org | 1938242 | 2014-01-14 20:51:26 +0000 | [diff] [blame] | 10 | #include "SkWriter32.h" |
reed@google.com | fd0ffcf | 2011-06-21 15:43:11 +0000 | [diff] [blame] | 11 | |
| 12 | /* |
| 13 | * Strings are stored as: length[4-bytes] + string_data + '\0' + pad_to_mul_4 |
| 14 | */ |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 15 | |
| 16 | const char* SkReader32::readString(size_t* outLen) { |
reed@google.com | fd0ffcf | 2011-06-21 15:43:11 +0000 | [diff] [blame] | 17 | size_t len = this->readInt(); |
| 18 | const void* ptr = this->peek(); |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 19 | |
commit-bot@chromium.org | 1938242 | 2014-01-14 20:51:26 +0000 | [diff] [blame] | 20 | // skip over the string + '\0' and then pad to a multiple of 4 |
reed@google.com | fd0ffcf | 2011-06-21 15:43:11 +0000 | [diff] [blame] | 21 | size_t alignedSize = SkAlign4(len + 1); |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 22 | this->skip(alignedSize); |
| 23 | |
| 24 | if (outLen) { |
| 25 | *outLen = len; |
| 26 | } |
| 27 | return (const char*)ptr; |
| 28 | } |
| 29 | |
reed@google.com | fd0ffcf | 2011-06-21 15:43:11 +0000 | [diff] [blame] | 30 | size_t SkReader32::readIntoString(SkString* copy) { |
| 31 | size_t len; |
| 32 | const char* ptr = this->readString(&len); |
| 33 | if (copy) { |
| 34 | copy->set(ptr, len); |
| 35 | } |
| 36 | return len; |
| 37 | } |
| 38 | |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 39 | void SkWriter32::writeString(const char str[], size_t len) { |
commit-bot@chromium.org | 47fa136 | 2013-08-09 16:03:05 +0000 | [diff] [blame] | 40 | if (NULL == str) { |
mtklein@google.com | 0038c12 | 2013-08-15 21:01:32 +0000 | [diff] [blame] | 41 | str = ""; |
| 42 | len = 0; |
commit-bot@chromium.org | 47fa136 | 2013-08-09 16:03:05 +0000 | [diff] [blame] | 43 | } |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 44 | if ((long)len < 0) { |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 45 | len = strlen(str); |
| 46 | } |
reed@google.com | fd0ffcf | 2011-06-21 15:43:11 +0000 | [diff] [blame] | 47 | this->write32(len); |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 48 | // add 1 since we also write a terminating 0 |
reed@google.com | fd0ffcf | 2011-06-21 15:43:11 +0000 | [diff] [blame] | 49 | size_t alignedLen = SkAlign4(len + 1); |
| 50 | char* ptr = (char*)this->reserve(alignedLen); |
scroggo@google.com | dd39488 | 2012-07-24 20:47:55 +0000 | [diff] [blame] | 51 | { |
| 52 | // Write the terminating 0 and fill in the rest with zeroes |
| 53 | uint32_t* padding = (uint32_t*)(ptr + (alignedLen - 4)); |
| 54 | *padding = 0; |
scroggo@google.com | e9617eb | 2012-07-23 13:44:10 +0000 | [diff] [blame] | 55 | } |
scroggo@google.com | dd39488 | 2012-07-24 20:47:55 +0000 | [diff] [blame] | 56 | // Copy the string itself. |
| 57 | memcpy(ptr, str, len); |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 58 | } |
| 59 | |
| 60 | size_t SkWriter32::WriteStringSize(const char* str, size_t len) { |
| 61 | if ((long)len < 0) { |
| 62 | SkASSERT(str); |
| 63 | len = strlen(str); |
| 64 | } |
reed@google.com | fd0ffcf | 2011-06-21 15:43:11 +0000 | [diff] [blame] | 65 | const size_t lenBytes = 4; // we use 4 bytes to record the length |
reed@google.com | dde0956 | 2011-05-23 12:21:05 +0000 | [diff] [blame] | 66 | // add 1 since we also write a terminating 0 |
| 67 | return SkAlign4(lenBytes + len + 1); |
| 68 | } |
commit-bot@chromium.org | 046f1f6 | 2014-02-11 10:17:02 +0000 | [diff] [blame^] | 69 | |
| 70 | void SkWriter32::growToAtLeast(size_t size) { |
| 71 | bool wasExternal = (fExternal != NULL) && (fData == fExternal); |
| 72 | // cause the buffer to grow |
| 73 | fInternal.setCount(size); |
| 74 | fData = fInternal.begin(); |
| 75 | if (wasExternal) { |
| 76 | // we were external, so copy in the data |
| 77 | memcpy(fData, fExternal, fUsed); |
| 78 | } |
| 79 | // Find out the size the buffer grew to, it may be more than we asked for. |
| 80 | fCapacity = fInternal.reserved(); |
| 81 | // Expand the array so all reserved space is "used", we maintain the |
| 82 | // amount we have written manually outside the array |
| 83 | fInternal.setCount(fCapacity); |
| 84 | SkASSERT(fInternal.count() == fCapacity); |
| 85 | SkASSERT(fInternal.reserved() == fCapacity); |
| 86 | } |