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author | Svetoslav <svetoslavganov@google.com> | 2014-09-04 21:17:17 -0700 |
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committer | Svet Ganov <svetoslavganov@google.com> | 2014-09-09 09:38:07 -0700 |
commit | 62ce332c141cf7bc7200c4c87d63e395874fc3ec (patch) | |
tree | b07d01bf00e4cdd04ed74514e392578ceb9409f7 /core/jni/android | |
parent | b86d5b57aa7e15455fc16e558121fa84c81ca38b (diff) | |
download | frameworks_base-62ce332c141cf7bc7200c4c87d63e395874fc3ec.zip frameworks_base-62ce332c141cf7bc7200c4c87d63e395874fc3ec.tar.gz frameworks_base-62ce332c141cf7bc7200c4c87d63e395874fc3ec.tar.bz2 |
Trim unnecessary pages when printing.
A user may request a subset of the document's pages to be printed.
In this case the expectation is that the resulting document does
not include not selected pages. While print serivices can do the
trimming themselves or the printer may do so, moving, potantually
many, redundant pages is inefficient. The real problem is when
saving to a PDF file where the saved file must not have the pages
the user did not select. This change adds shredding of undesired
pages from the PDF before saving it or passing it to a print service.
:
bug:17285994
Change-Id: I7deba535af99457bea3c118202314f0f3812e809
Diffstat (limited to 'core/jni/android')
-rw-r--r-- | core/jni/android/graphics/pdf/PdfEditor.cpp | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/core/jni/android/graphics/pdf/PdfEditor.cpp b/core/jni/android/graphics/pdf/PdfEditor.cpp new file mode 100644 index 0000000..5f60c9e --- /dev/null +++ b/core/jni/android/graphics/pdf/PdfEditor.cpp @@ -0,0 +1,161 @@ +/* + * Copyright (C) 2014 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "jni.h" +#include "JNIHelp.h" +#include "fpdfview.h" +#include "fpdfedit.h" +#include "fpdfsave.h" + +#include <android_runtime/AndroidRuntime.h> +#include <vector> +#include <utils/Log.h> +#include <unistd.h> +#include <sys/types.h> +#include <unistd.h> + +namespace android { + +static Mutex sLock; + +static int sUnmatchedInitRequestCount = 0; + +static void initializeLibraryIfNeeded() { + Mutex::Autolock _l(sLock); + if (sUnmatchedInitRequestCount == 0) { + FPDF_InitLibrary(NULL); + } + sUnmatchedInitRequestCount++; +} + +static void destroyLibraryIfNeeded() { + Mutex::Autolock _l(sLock); + sUnmatchedInitRequestCount--; + if (sUnmatchedInitRequestCount == 0) { + FPDF_DestroyLibrary(); + } +} + +static int getBlock(void* param, unsigned long position, unsigned char* outBuffer, + unsigned long size) { + const int fd = reinterpret_cast<intptr_t>(param); + const int readCount = pread(fd, outBuffer, size, position); + if (readCount < 0) { + ALOGE("Cannot read from file descriptor. Error:%d", errno); + return 0; + } + return 1; +} + +static jlong nativeOpen(JNIEnv* env, jclass thiz, jint fd, jlong size) { + initializeLibraryIfNeeded(); + + FPDF_FILEACCESS loader; + loader.m_FileLen = size; + loader.m_Param = reinterpret_cast<void*>(intptr_t(fd)); + loader.m_GetBlock = &getBlock; + + FPDF_DOCUMENT document = FPDF_LoadCustomDocument(&loader, NULL); + + if (!document) { + const long error = FPDF_GetLastError(); + jniThrowException(env, "java/io/IOException", + "cannot create document. Error:" + error); + destroyLibraryIfNeeded(); + return -1; + } + + return reinterpret_cast<jlong>(document); +} + +static void nativeClose(JNIEnv* env, jclass thiz, jlong documentPtr) { + FPDF_DOCUMENT document = reinterpret_cast<FPDF_DOCUMENT>(documentPtr); + FPDF_CloseDocument(document); + destroyLibraryIfNeeded(); +} + +static jint nativeGetPageCount(JNIEnv* env, jclass thiz, jlong documentPtr) { + FPDF_DOCUMENT document = reinterpret_cast<FPDF_DOCUMENT>(documentPtr); + return FPDF_GetPageCount(document); +} + +static jint nativeRemovePage(JNIEnv* env, jclass thiz, jlong documentPtr, jint pageIndex) { + FPDF_DOCUMENT document = reinterpret_cast<FPDF_DOCUMENT>(documentPtr); + FPDFPage_Delete(document, pageIndex); + return FPDF_GetPageCount(document); +} + +struct PdfToFdWriter : FPDF_FILEWRITE { + int dstFd; +}; + +static bool writeAllBytes(const int fd, const void* buffer, const size_t byteCount) { + char* writeBuffer = static_cast<char*>(const_cast<void*>(buffer)); + size_t remainingBytes = byteCount; + while (remainingBytes > 0) { + ssize_t writtenByteCount = write(fd, writeBuffer, remainingBytes); + if (writtenByteCount == -1) { + if (errno == EINTR) { + continue; + } + __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, + "Error writing to buffer: %d", errno); + return false; + } + remainingBytes -= writtenByteCount; + writeBuffer += writtenByteCount; + } + return true; +} + +static int writeBlock(FPDF_FILEWRITE* owner, const void* buffer, unsigned long size) { + const PdfToFdWriter* writer = reinterpret_cast<PdfToFdWriter*>(owner); + const bool success = writeAllBytes(writer->dstFd, buffer, size); + if (success < 0) { + ALOGE("Cannot write to file descriptor. Error:%d", errno); + return 0; + } + return 1; +} + +static void nativeWrite(JNIEnv* env, jclass thiz, jlong documentPtr, jint fd) { + FPDF_DOCUMENT document = reinterpret_cast<FPDF_DOCUMENT>(documentPtr); + PdfToFdWriter writer; + writer.dstFd = fd; + writer.WriteBlock = &writeBlock; + const bool success = FPDF_SaveAsCopy(document, &writer, FPDF_NO_INCREMENTAL); + if (!success) { + jniThrowException(env, "java/io/IOException", + "cannot write to fd. Error:" + errno); + destroyLibraryIfNeeded(); + } +} + +static JNINativeMethod gPdfEditor_Methods[] = { + {"nativeOpen", "(IJ)J", (void*) nativeOpen}, + {"nativeClose", "(J)V", (void*) nativeClose}, + {"nativeGetPageCount", "(J)I", (void*) nativeGetPageCount}, + {"nativeRemovePage", "(JI)I", (void*) nativeRemovePage}, + {"nativeWrite", "(JI)V", (void*) nativeWrite} +}; + +int register_android_graphics_pdf_PdfEditor(JNIEnv* env) { + return android::AndroidRuntime::registerNativeMethods( + env, "android/graphics/pdf/PdfEditor", gPdfEditor_Methods, + NELEM(gPdfEditor_Methods)); +}; + +}; |