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// Copyright 2014 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
#ifndef PUBLIC_FPDF_TEXT_H_
#define PUBLIC_FPDF_TEXT_H_
// NOLINTNEXTLINE(build/include)
#include "fpdfview.h"
// Exported Functions
#ifdef __cplusplus
extern "C" {
#endif
// Function: FPDFText_LoadPage
// Prepare information about all characters in a page.
// Parameters:
// page - Handle to the page. Returned by FPDF_LoadPage function
// (in FPDFVIEW module).
// Return value:
// A handle to the text page information structure.
// NULL if something goes wrong.
// Comments:
// Application must call FPDFText_ClosePage to release the text page
// information.
//
FPDF_EXPORT FPDF_TEXTPAGE FPDF_CALLCONV FPDFText_LoadPage(FPDF_PAGE page);
// Function: FPDFText_ClosePage
// Release all resources allocated for a text page information
// structure.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// Return Value:
// None.
//
FPDF_EXPORT void FPDF_CALLCONV FPDFText_ClosePage(FPDF_TEXTPAGE text_page);
// Function: FPDFText_CountChars
// Get number of characters in a page.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// Return value:
// Number of characters in the page. Return -1 for error.
// Generated characters, like additional space characters, new line
// characters, are also counted.
// Comments:
// Characters in a page form a "stream", inside the stream, each
// character has an index.
// We will use the index parameters in many of FPDFTEXT functions. The
// first character in the page
// has an index value of zero.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFText_CountChars(FPDF_TEXTPAGE text_page);
// Function: FPDFText_GetUnicode
// Get Unicode of a character in a page.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// index - Zero-based index of the character.
// Return value:
// The Unicode of the particular character.
// If a character is not encoded in Unicode and Foxit engine can't
// convert to Unicode,
// the return value will be zero.
//
FPDF_EXPORT unsigned int FPDF_CALLCONV
FPDFText_GetUnicode(FPDF_TEXTPAGE text_page, int index);
// Function: FPDFText_GetFontSize
// Get the font size of a particular character.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// index - Zero-based index of the character.
// Return value:
// The font size of the particular character, measured in points (about
// 1/72 inch).
// This is the typographic size of the font (so called "em size").
//
FPDF_EXPORT double FPDF_CALLCONV FPDFText_GetFontSize(FPDF_TEXTPAGE text_page,
int index);
// Experimental API.
// Function: FPDFText_GetFontInfo
// Get the font name and flags of a particular character.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// index - Zero-based index of the character.
// buffer - A buffer receiving the font name.
// buflen - The length of |buffer| in bytes.
// flags - Optional pointer to an int receiving the font flags.
// These flags should be interpreted per PDF spec 1.7 Section 5.7.1
// Font Descriptor Flags.
// Return value:
// On success, return the length of the font name, including the
// trailing NUL character, in bytes. If this length is less than or
// equal to |length|, |buffer| is set to the font name, |flags| is
// set to the font flags. |buffer| is in UTF-8 encoding. Return 0 on
// failure.
FPDF_EXPORT unsigned long FPDF_CALLCONV
FPDFText_GetFontInfo(FPDF_TEXTPAGE text_page,
int index,
void* buffer,
unsigned long buflen,
int* flags);
// Function: FPDFText_GetCharBox
// Get bounding box of a particular character.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// index - Zero-based index of the character.
// left - Pointer to a double number receiving left position
// of the character box.
// right - Pointer to a double number receiving right position
// of the character box.
// bottom - Pointer to a double number receiving bottom position
// of the character box.
// top - Pointer to a double number receiving top position of
// the character box.
// Return Value:
// On success, return TRUE and fill in |left|, |right|, |bottom|, and
// |top|. If |text_page| is invalid, or if |index| is out of bounds,
// then return FALSE, and the out parameters remain unmodified.
// Comments:
// All positions are measured in PDF "user space".
//
FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV FPDFText_GetCharBox(FPDF_TEXTPAGE text_page,
int index,
double* left,
double* right,
double* bottom,
double* top);
// Function: FPDFText_GetCharOrigin
// Get origin of a particular character.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// index - Zero-based index of the character.
// x - Pointer to a double number receiving x coordinate of
// the character origin.
// y - Pointer to a double number receiving y coordinate of
// the character origin.
// Return Value:
// Whether the call succeeded. If false, x and y are unchanged.
// Comments:
// All positions are measured in PDF "user space".
//
FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
FPDFText_GetCharOrigin(FPDF_TEXTPAGE text_page,
int index,
double* x,
double* y);
// Function: FPDFText_GetCharIndexAtPos
// Get the index of a character at or nearby a certain position on the
// page.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// x - X position in PDF "user space".
// y - Y position in PDF "user space".
// xTolerance - An x-axis tolerance value for character hit
// detection, in point unit.
// yTolerance - A y-axis tolerance value for character hit
// detection, in point unit.
// Return Value:
// The zero-based index of the character at, or nearby the point (x,y).
// If there is no character at or nearby the point, return value will
// be -1.
// If an error occurs, -3 will be returned.
//
FPDF_EXPORT int FPDF_CALLCONV
FPDFText_GetCharIndexAtPos(FPDF_TEXTPAGE text_page,
double x,
double y,
double xTolerance,
double yTolerance);
// Function: FPDFText_GetText
// Extract unicode text string from the page.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// start_index - Index for the start characters.
// count - Number of characters to be extracted.
// result - A buffer (allocated by application) receiving the
// extracted unicodes.
// The size of the buffer must be able to hold the
// number of characters plus a terminator.
// Return Value:
// Number of characters written into the result buffer, including the
// trailing terminator.
// Comments:
// This function ignores characters without unicode information.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFText_GetText(FPDF_TEXTPAGE text_page,
int start_index,
int count,
unsigned short* result);
// Function: FPDFText_CountRects
// Count number of rectangular areas occupied by a segment of texts.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// start_index - Index for the start characters.
// count - Number of characters.
// Return value:
// Number of rectangles. Zero for error.
// Comments:
// This function, along with FPDFText_GetRect can be used by
// applications to detect the position
// on the page for a text segment, so proper areas can be highlighted
// or something.
// FPDFTEXT will automatically merge small character boxes into bigger
// one if those characters
// are on the same line and use same font settings.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFText_CountRects(FPDF_TEXTPAGE text_page,
int start_index,
int count);
// Function: FPDFText_GetRect
// Get a rectangular area from the result generated by
// FPDFText_CountRects.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// rect_index - Zero-based index for the rectangle.
// left - Pointer to a double value receiving the rectangle
// left boundary.
// top - Pointer to a double value receiving the rectangle
// top boundary.
// right - Pointer to a double value receiving the rectangle
// right boundary.
// bottom - Pointer to a double value receiving the rectangle
// bottom boundary.
// Return Value:
// On success, return TRUE and fill in |left|, |top|, |right|, and
// |bottom|. If |text_page| is invalid then return FALSE, and the out
// parameters remain unmodified. If |text_page| is valid but
// |rect_index| is out of bounds, then return FALSE and set the out
// parameters to 0.
//
FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV FPDFText_GetRect(FPDF_TEXTPAGE text_page,
int rect_index,
double* left,
double* top,
double* right,
double* bottom);
// Function: FPDFText_GetBoundedText
// Extract unicode text within a rectangular boundary on the page.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// left - Left boundary.
// top - Top boundary.
// right - Right boundary.
// bottom - Bottom boundary.
// buffer - A unicode buffer.
// buflen - Number of characters (not bytes) for the buffer,
// excluding an additional terminator.
// Return Value:
// If buffer is NULL or buflen is zero, return number of characters
// (not bytes) of text present within
// the rectangle, excluding a terminating NUL. Generally you should
// pass a buffer at least one larger
// than this if you want a terminating NUL, which will be provided if
// space is available.
// Otherwise, return number of characters copied into the buffer,
// including the terminating NUL
// when space for it is available.
// Comment:
// If the buffer is too small, as much text as will fit is copied into
// it.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFText_GetBoundedText(FPDF_TEXTPAGE text_page,
double left,
double top,
double right,
double bottom,
unsigned short* buffer,
int buflen);
// Flags used by FPDFText_FindStart function.
#define FPDF_MATCHCASE \
0x00000001 // If not set, it will not match case by default.
#define FPDF_MATCHWHOLEWORD \
0x00000002 // If not set, it will not match the whole word by default.
// Function: FPDFText_FindStart
// Start a search.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// findwhat - A unicode match pattern.
// flags - Option flags.
// start_index - Start from this character. -1 for end of the page.
// Return Value:
// A handle for the search context. FPDFText_FindClose must be called
// to release this handle.
//
FPDF_EXPORT FPDF_SCHHANDLE FPDF_CALLCONV
FPDFText_FindStart(FPDF_TEXTPAGE text_page,
FPDF_WIDESTRING findwhat,
unsigned long flags,
int start_index);
// Function: FPDFText_FindNext
// Search in the direction from page start to end.
// Parameters:
// handle - A search context handle returned by
// FPDFText_FindStart.
// Return Value:
// Whether a match is found.
//
FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV FPDFText_FindNext(FPDF_SCHHANDLE handle);
// Function: FPDFText_FindPrev
// Search in the direction from page end to start.
// Parameters:
// handle - A search context handle returned by
// FPDFText_FindStart.
// Return Value:
// Whether a match is found.
//
FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV FPDFText_FindPrev(FPDF_SCHHANDLE handle);
// Function: FPDFText_GetSchResultIndex
// Get the starting character index of the search result.
// Parameters:
// handle - A search context handle returned by
// FPDFText_FindStart.
// Return Value:
// Index for the starting character.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFText_GetSchResultIndex(FPDF_SCHHANDLE handle);
// Function: FPDFText_GetSchCount
// Get the number of matched characters in the search result.
// Parameters:
// handle - A search context handle returned by
// FPDFText_FindStart.
// Return Value:
// Number of matched characters.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFText_GetSchCount(FPDF_SCHHANDLE handle);
// Function: FPDFText_FindClose
// Release a search context.
// Parameters:
// handle - A search context handle returned by
// FPDFText_FindStart.
// Return Value:
// None.
//
FPDF_EXPORT void FPDF_CALLCONV FPDFText_FindClose(FPDF_SCHHANDLE handle);
// Function: FPDFLink_LoadWebLinks
// Prepare information about weblinks in a page.
// Parameters:
// text_page - Handle to a text page information structure.
// Returned by FPDFText_LoadPage function.
// Return Value:
// A handle to the page's links information structure.
// NULL if something goes wrong.
// Comments:
// Weblinks are those links implicitly embedded in PDF pages. PDF also
// has a type of
// annotation called "link", FPDFTEXT doesn't deal with that kind of
// link.
// FPDFTEXT weblink feature is useful for automatically detecting links
// in the page
// contents. For example, things like "http://www.foxitsoftware.com"
// will be detected,
// so applications can allow user to click on those characters to
// activate the link,
// even the PDF doesn't come with link annotations.
//
// FPDFLink_CloseWebLinks must be called to release resources.
//
FPDF_EXPORT FPDF_PAGELINK FPDF_CALLCONV
FPDFLink_LoadWebLinks(FPDF_TEXTPAGE text_page);
// Function: FPDFLink_CountWebLinks
// Count number of detected web links.
// Parameters:
// link_page - Handle returned by FPDFLink_LoadWebLinks.
// Return Value:
// Number of detected web links.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFLink_CountWebLinks(FPDF_PAGELINK link_page);
// Function: FPDFLink_GetURL
// Fetch the URL information for a detected web link.
// Parameters:
// link_page - Handle returned by FPDFLink_LoadWebLinks.
// link_index - Zero-based index for the link.
// buffer - A unicode buffer for the result.
// buflen - Number of characters (not bytes) for the buffer,
// including an additional terminator.
// Return Value:
// If |buffer| is NULL or |buflen| is zero, return the number of
// characters (not bytes) needed to buffer the result (an additional
// terminator is included in this count).
// Otherwise, copy the result into |buffer|, truncating at |buflen| if
// the result is too large to fit, and return the number of characters
// actually copied into the buffer (the additional terminator is also
// included in this count).
// If |link_index| does not correspond to a valid link, then the result
// is an empty string.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFLink_GetURL(FPDF_PAGELINK link_page,
int link_index,
unsigned short* buffer,
int buflen);
// Function: FPDFLink_CountRects
// Count number of rectangular areas for the link.
// Parameters:
// link_page - Handle returned by FPDFLink_LoadWebLinks.
// link_index - Zero-based index for the link.
// Return Value:
// Number of rectangular areas for the link. If |link_index| does
// not correspond to a valid link, then 0 is returned.
//
FPDF_EXPORT int FPDF_CALLCONV FPDFLink_CountRects(FPDF_PAGELINK link_page,
int link_index);
// Function: FPDFLink_GetRect
// Fetch the boundaries of a rectangle for a link.
// Parameters:
// link_page - Handle returned by FPDFLink_LoadWebLinks.
// link_index - Zero-based index for the link.
// rect_index - Zero-based index for a rectangle.
// left - Pointer to a double value receiving the rectangle
// left boundary.
// top - Pointer to a double value receiving the rectangle
// top boundary.
// right - Pointer to a double value receiving the rectangle
// right boundary.
// bottom - Pointer to a double value receiving the rectangle
// bottom boundary.
// Return Value:
// On success, return TRUE and fill in |left|, |top|, |right|, and
// |bottom|. If |link_page| is invalid or if |link_index| does not
// correspond to a valid link, then return FALSE, and the out
// parameters remain unmodified.
//
FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV FPDFLink_GetRect(FPDF_PAGELINK link_page,
int link_index,
int rect_index,
double* left,
double* top,
double* right,
double* bottom);
// Function: FPDFLink_CloseWebLinks
// Release resources used by weblink feature.
// Parameters:
// link_page - Handle returned by FPDFLink_LoadWebLinks.
// Return Value:
// None.
//
FPDF_EXPORT void FPDF_CALLCONV FPDFLink_CloseWebLinks(FPDF_PAGELINK link_page);
#ifdef __cplusplus
}
#endif
#endif // PUBLIC_FPDF_TEXT_H_