/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */ /* cairo - a vector graphics library with display and print output * * Copyright © 2002 University of Southern California * Copyright © 2005 Red Hat, Inc. * Copyright © 2007 Adrian Johnson * * This library is free software; you can redistribute it and/or * modify it either under the terms of the GNU Lesser General Public * License version 2.1 as published by the Free Software Foundation * (the "LGPL") or, at your option, under the terms of the Mozilla * Public License Version 1.1 (the "MPL"). If you do not alter this * notice, a recipient may use your version of this file under either * the MPL or the LGPL. * * You should have received a copy of the LGPL along with this library * in the file COPYING-LGPL-2.1; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * You should have received a copy of the MPL along with this library * in the file COPYING-MPL-1.1 * * The contents of this file are subject to the Mozilla Public License * Version 1.1 (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.mozilla.org/MPL/ * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY * OF ANY KIND, either express or implied. See the LGPL or the MPL for * the specific language governing rights and limitations. * * The Original Code is the cairo graphics library. * * The Initial Developer of the Original Code is University of Southern * California. * * Contributor(s): * Carl D. Worth <cworth@cworth.org> * Adrian Johnson <ajohnson@redneon.com> */ #include "cairoint.h" COMPILE_TIME_ASSERT (CAIRO_STATUS_LAST_STATUS < CAIRO_INT_STATUS_UNSUPPORTED); COMPILE_TIME_ASSERT (CAIRO_INT_STATUS_LAST_STATUS <= 127); /* Public stuff */ /** * cairo_status_to_string: * @status: a cairo status * * Provides a human-readable description of a #cairo_status_t. * * Returns: a string representation of the status */ const char * cairo_status_to_string (cairo_status_t status) { switch (status) { case CAIRO_STATUS_SUCCESS: return "success"; case CAIRO_STATUS_NO_MEMORY: return "out of memory"; case CAIRO_STATUS_INVALID_RESTORE: return "cairo_restore without matching cairo_save"; case CAIRO_STATUS_INVALID_POP_GROUP: return "cairo_pop_group without matching cairo_push_group"; case CAIRO_STATUS_NO_CURRENT_POINT: return "no current point defined"; case CAIRO_STATUS_INVALID_MATRIX: return "invalid matrix (not invertible)"; case CAIRO_STATUS_INVALID_STATUS: return "invalid value for an input cairo_status_t"; case CAIRO_STATUS_NULL_POINTER: return "NULL pointer"; case CAIRO_STATUS_INVALID_STRING: return "input string not valid UTF-8"; case CAIRO_STATUS_INVALID_PATH_DATA: return "input path data not valid"; case CAIRO_STATUS_READ_ERROR: return "error while reading from input stream"; case CAIRO_STATUS_WRITE_ERROR: return "error while writing to output stream"; case CAIRO_STATUS_SURFACE_FINISHED: return "the target surface has been finished"; case CAIRO_STATUS_SURFACE_TYPE_MISMATCH: return "the surface type is not appropriate for the operation"; case CAIRO_STATUS_PATTERN_TYPE_MISMATCH: return "the pattern type is not appropriate for the operation"; case CAIRO_STATUS_INVALID_CONTENT: return "invalid value for an input cairo_content_t"; case CAIRO_STATUS_INVALID_FORMAT: return "invalid value for an input cairo_format_t"; case CAIRO_STATUS_INVALID_VISUAL: return "invalid value for an input Visual*"; case CAIRO_STATUS_FILE_NOT_FOUND: return "file not found"; case CAIRO_STATUS_INVALID_DASH: return "invalid value for a dash setting"; case CAIRO_STATUS_INVALID_DSC_COMMENT: return "invalid value for a DSC comment"; case CAIRO_STATUS_INVALID_INDEX: return "invalid index passed to getter"; case CAIRO_STATUS_CLIP_NOT_REPRESENTABLE: return "clip region not representable in desired format"; case CAIRO_STATUS_TEMP_FILE_ERROR: return "error creating or writing to a temporary file"; case CAIRO_STATUS_INVALID_STRIDE: return "invalid value for stride"; case CAIRO_STATUS_FONT_TYPE_MISMATCH: return "the font type is not appropriate for the operation"; case CAIRO_STATUS_USER_FONT_IMMUTABLE: return "the user-font is immutable"; case CAIRO_STATUS_USER_FONT_ERROR: return "error occurred in a user-font callback function"; case CAIRO_STATUS_NEGATIVE_COUNT: return "negative number used where it is not allowed"; case CAIRO_STATUS_INVALID_CLUSTERS: return "input clusters do not represent the accompanying text and glyph arrays"; case CAIRO_STATUS_INVALID_SLANT: return "invalid value for an input #cairo_font_slant_t"; case CAIRO_STATUS_INVALID_WEIGHT: return "input value for an input #cairo_font_weight_t"; } return "<unknown error status>"; } /** * cairo_glyph_allocate: * @num_glyphs: number of glyphs to allocate * * Allocates an array of #cairo_glyph_t's. * This function is only useful in implementations of * #cairo_user_scaled_font_text_to_glyphs_func_t where the user * needs to allocate an array of glyphs that cairo will free. * For all other uses, user can use their own allocation method * for glyphs. * * This function returns %NULL if @num_glyphs is not positive, * or if out of memory. That means, the %NULL return value * signals out-of-memory only if @num_glyphs was positive. * * Returns: the newly allocated array of glyphs that should be * freed using cairo_glyph_free() * * Since: 1.8 */ cairo_glyph_t * cairo_glyph_allocate (int num_glyphs) { if (num_glyphs <= 0) return NULL; return _cairo_malloc_ab (num_glyphs, sizeof (cairo_glyph_t)); } slim_hidden_def (cairo_glyph_allocate); /** * cairo_glyph_free: * @glyphs: array of glyphs to free, or %NULL * * Frees an array of #cairo_glyph_t's allocated using cairo_glyph_allocate(). * This function is only useful to free glyph array returned * by cairo_scaled_font_text_to_glyphs() where cairo returns * an array of glyphs that the user will free. * For all other uses, user can use their own allocation method * for glyphs. * * Since: 1.8 */ void cairo_glyph_free (cairo_glyph_t *glyphs) { if (glyphs) free (glyphs); } slim_hidden_def (cairo_glyph_free); /** * cairo_text_cluster_allocate: * @num_clusters: number of text_clusters to allocate * * Allocates an array of #cairo_text_cluster_t's. * This function is only useful in implementations of * #cairo_user_scaled_font_text_to_glyphs_func_t where the user * needs to allocate an array of text clusters that cairo will free. * For all other uses, user can use their own allocation method * for text clusters. * * This function returns %NULL if @num_clusters is not positive, * or if out of memory. That means, the %NULL return value * signals out-of-memory only if @num_clusters was positive. * * Returns: the newly allocated array of text clusters that should be * freed using cairo_text_cluster_free() * * Since: 1.8 */ cairo_text_cluster_t * cairo_text_cluster_allocate (int num_clusters) { if (num_clusters <= 0) return NULL; return _cairo_malloc_ab (num_clusters, sizeof (cairo_text_cluster_t)); } slim_hidden_def (cairo_text_cluster_allocate); /** * cairo_text_cluster_free: * @clusters: array of text clusters to free, or %NULL * * Frees an array of #cairo_text_cluster's allocated using cairo_text_cluster_allocate(). * This function is only useful to free text cluster array returned * by cairo_scaled_font_text_to_glyphs() where cairo returns * an array of text clusters that the user will free. * For all other uses, user can use their own allocation method * for text clusters. * * Since: 1.8 */ void cairo_text_cluster_free (cairo_text_cluster_t *clusters) { if (clusters) free (clusters); } slim_hidden_def (cairo_text_cluster_free); /* Private stuff */ /** * _cairo_validate_text_clusters: * @utf8: UTF-8 text * @utf8_len: length of @utf8 in bytes * @glyphs: array of glyphs * @num_glyphs: number of glyphs * @clusters: array of cluster mapping information * @num_clusters: number of clusters in the mapping * @cluster_flags: cluster flags * * Check that clusters cover the entire glyphs and utf8 arrays, * and that cluster boundaries are UTF-8 boundaries. * * Return value: %CAIRO_STATUS_SUCCESS upon success, or * %CAIRO_STATUS_INVALID_CLUSTERS on error. * The error is either invalid UTF-8 input, * or bad cluster mapping. */ cairo_status_t _cairo_validate_text_clusters (const char *utf8, int utf8_len, const cairo_glyph_t *glyphs, int num_glyphs, const cairo_text_cluster_t *clusters, int num_clusters, cairo_text_cluster_flags_t cluster_flags) { cairo_status_t status; unsigned int n_bytes = 0; unsigned int n_glyphs = 0; int i; for (i = 0; i < num_clusters; i++) { int cluster_bytes = clusters[i].num_bytes; int cluster_glyphs = clusters[i].num_glyphs; if (cluster_bytes < 0 || cluster_glyphs < 0) goto BAD; /* A cluster should cover at least one character or glyph. * I can't see any use for a 0,0 cluster. * I can't see an immediate use for a zero-text cluster * right now either, but they don't harm. * Zero-glyph clusters on the other hand are useful for * things like U+200C ZERO WIDTH NON-JOINER */ if (cluster_bytes == 0 && cluster_glyphs == 0) goto BAD; /* Since n_bytes and n_glyphs are unsigned, but the rest of * values involved are signed, we can detect overflow easily */ if (n_bytes+cluster_bytes > (unsigned int)utf8_len || n_glyphs+cluster_glyphs > (unsigned int)num_glyphs) goto BAD; /* Make sure we've got valid UTF-8 for the cluster */ status = _cairo_utf8_to_ucs4 (utf8+n_bytes, cluster_bytes, NULL, NULL); if (status) return CAIRO_STATUS_INVALID_CLUSTERS; n_bytes += cluster_bytes ; n_glyphs += cluster_glyphs; } if (n_bytes != (unsigned int) utf8_len || n_glyphs != (unsigned int) num_glyphs) { BAD: return CAIRO_STATUS_INVALID_CLUSTERS; } return CAIRO_STATUS_SUCCESS; } /** * _cairo_operator_bounded_by_mask: * @op: a #cairo_operator_t * * A bounded operator is one where mask pixel * of zero results in no effect on the destination image. * * Unbounded operators often require special handling; if you, for * example, draw trapezoids with an unbounded operator, the effect * extends past the bounding box of the trapezoids. * * Return value: %TRUE if the operator is bounded by the mask operand **/ cairo_bool_t _cairo_operator_bounded_by_mask (cairo_operator_t op) { switch (op) { case CAIRO_OPERATOR_CLEAR: case CAIRO_OPERATOR_SOURCE: case CAIRO_OPERATOR_OVER: case CAIRO_OPERATOR_ATOP: case CAIRO_OPERATOR_DEST: case CAIRO_OPERATOR_DEST_OVER: case CAIRO_OPERATOR_DEST_OUT: case CAIRO_OPERATOR_XOR: case CAIRO_OPERATOR_ADD: case CAIRO_OPERATOR_SATURATE: return TRUE; case CAIRO_OPERATOR_OUT: case CAIRO_OPERATOR_IN: case CAIRO_OPERATOR_DEST_IN: case CAIRO_OPERATOR_DEST_ATOP: return FALSE; } ASSERT_NOT_REACHED; return FALSE; } /** * _cairo_operator_bounded_by_source: * @op: a #cairo_operator_t * * A bounded operator is one where source pixels of zero * (in all four components, r, g, b and a) effect no change * in the resulting destination image. * * Unbounded operators often require special handling; if you, for * example, copy a surface with the SOURCE operator, the effect * extends past the bounding box of the source surface. * * Return value: %TRUE if the operator is bounded by the source operand **/ cairo_bool_t _cairo_operator_bounded_by_source (cairo_operator_t op) { switch (op) { case CAIRO_OPERATOR_OVER: case CAIRO_OPERATOR_ATOP: case CAIRO_OPERATOR_DEST: case CAIRO_OPERATOR_DEST_OVER: case CAIRO_OPERATOR_DEST_OUT: case CAIRO_OPERATOR_XOR: case CAIRO_OPERATOR_ADD: case CAIRO_OPERATOR_SATURATE: return TRUE; case CAIRO_OPERATOR_CLEAR: case CAIRO_OPERATOR_SOURCE: case CAIRO_OPERATOR_OUT: case CAIRO_OPERATOR_IN: case CAIRO_OPERATOR_DEST_IN: case CAIRO_OPERATOR_DEST_ATOP: return FALSE; } ASSERT_NOT_REACHED; return FALSE; } void _cairo_restrict_value (double *value, double min, double max) { if (*value < min) *value = min; else if (*value > max) *value = max; } /* This function is identical to the C99 function lround(), except that it * performs arithmetic rounding (instead of away-from-zero rounding) and * has a valid input range of (INT_MIN, INT_MAX] instead of * [INT_MIN, INT_MAX]. It is much faster on both x86 and FPU-less systems * than other commonly used methods for rounding (lround, round, rint, lrint * or float (d + 0.5)). * * The reason why this function is much faster on x86 than other * methods is due to the fact that it avoids the fldcw instruction. * This instruction incurs a large performance penalty on modern Intel * processors due to how it prevents efficient instruction pipelining. * * The reason why this function is much faster on FPU-less systems is for * an entirely different reason. All common rounding methods involve multiple * floating-point operations. Each one of these operations has to be * emulated in software, which adds up to be a large performance penalty. * This function doesn't perform any floating-point calculations, and thus * avoids this penalty. */ int _cairo_lround (double d) { uint32_t top, shift_amount, output; union { double d; uint64_t ui64; uint32_t ui32[2]; } u; u.d = d; /* If the integer word order doesn't match the float word order, we swap * the words of the input double. This is needed because we will be * treating the whole double as a 64-bit unsigned integer. Notice that we * use WORDS_BIGENDIAN to detect the integer word order, which isn't * exactly correct because WORDS_BIGENDIAN refers to byte order, not word * order. Thus, we are making the assumption that the byte order is the * same as the integer word order which, on the modern machines that we * care about, is OK. */ #if ( defined(FLOAT_WORDS_BIGENDIAN) && !defined(WORDS_BIGENDIAN)) || \ (!defined(FLOAT_WORDS_BIGENDIAN) && defined(WORDS_BIGENDIAN)) { uint32_t temp = u.ui32[0]; u.ui32[0] = u.ui32[1]; u.ui32[1] = temp; } #endif #ifdef WORDS_BIGENDIAN #define MSW (0) /* Most Significant Word */ #define LSW (1) /* Least Significant Word */ #else #define MSW (1) #define LSW (0) #endif /* By shifting the most significant word of the input double to the * right 20 places, we get the very "top" of the double where the exponent * and sign bit lie. */ top = u.ui32[MSW] >> 20; /* Here, we calculate how much we have to shift the mantissa to normalize * it to an integer value. We extract the exponent "top" by masking out the * sign bit, then we calculate the shift amount by subtracting the exponent * from the bias. Notice that the correct bias for 64-bit doubles is * actually 1075, but we use 1053 instead for two reasons: * * 1) To perform rounding later on, we will first need the target * value in a 31.1 fixed-point format. Thus, the bias needs to be one * less: (1075 - 1: 1074). * * 2) To avoid shifting the mantissa as a full 64-bit integer (which is * costly on certain architectures), we break the shift into two parts. * First, the upper and lower parts of the mantissa are shifted * individually by a constant amount that all valid inputs will require * at the very least. This amount is chosen to be 21, because this will * allow the two parts of the mantissa to later be combined into a * single 32-bit representation, on which the remainder of the shift * will be performed. Thus, we decrease the bias by an additional 21: * (1074 - 21: 1053). */ shift_amount = 1053 - (top & 0x7FF); /* We are done with the exponent portion in "top", so here we shift it off * the end. */ top >>= 11; /* Before we perform any operations on the mantissa, we need to OR in * the implicit 1 at the top (see the IEEE-754 spec). We needn't mask * off the sign bit nor the exponent bits because these higher bits won't * make a bit of difference in the rest of our calculations. */ u.ui32[MSW] |= 0x100000; /* If the input double is negative, we have to decrease the mantissa * by a hair. This is an important part of performing arithmetic rounding, * as negative numbers must round towards positive infinity in the * halfwase case of -x.5. Since "top" contains only the sign bit at this * point, we can just decrease the mantissa by the value of "top". */ u.ui64 -= top; /* By decrementing "top", we create a bitmask with a value of either * 0x0 (if the input was negative) or 0xFFFFFFFF (if the input was positive * and thus the unsigned subtraction underflowed) that we'll use later. */ top--; /* Here, we shift the mantissa by the constant value as described above. * We can emulate a 64-bit shift right by 21 through shifting the top 32 * bits left 11 places and ORing in the bottom 32 bits shifted 21 places * to the right. Both parts of the mantissa are now packed into a single * 32-bit integer. Although we severely truncate the lower part in the * process, we still have enough significant bits to perform the conversion * without error (for all valid inputs). */ output = (u.ui32[MSW] << 11) | (u.ui32[LSW] >> 21); /* Next, we perform the shift that converts the X.Y fixed-point number * currently found in "output" to the desired 31.1 fixed-point format * needed for the following rounding step. It is important to consider * all possible values for "shift_amount" at this point: * * - {shift_amount < 0} Since shift_amount is an unsigned integer, it * really can't have a value less than zero. But, if the shift_amount * calculation above caused underflow (which would happen with * input > INT_MAX or input <= INT_MIN) then shift_amount will now be * a very large number, and so this shift will result in complete * garbage. But that's OK, as the input was out of our range, so our * output is undefined. * * - {shift_amount > 31} If the magnitude of the input was very small * (i.e. |input| << 1.0), shift_amount will have a value greater than * 31. Thus, this shift will also result in garbage. After performing * the shift, we will zero-out "output" if this is the case. * * - {0 <= shift_amount < 32} In this case, the shift will properly convert * the mantissa into a 31.1 fixed-point number. */ output >>= shift_amount; /* This is where we perform rounding with the 31.1 fixed-point number. * Since what we're after is arithmetic rounding, we simply add the single * fractional bit into the integer part of "output", and just keep the * integer part. */ output = (output >> 1) + (output & 1); /* Here, we zero-out the result if the magnitude if the input was very small * (as explained in the section above). Notice that all input out of the * valid range is also caught by this condition, which means we produce 0 * for all invalid input, which is a nice side effect. * * The most straightforward way to do this would be: * * if (shift_amount > 31) * output = 0; * * But we can use a little trick to avoid the potential branch. The * expression (shift_amount > 31) will be either 1 or 0, which when * decremented will be either 0x0 or 0xFFFFFFFF (unsigned underflow), * which can be used to conditionally mask away all the bits in "output" * (in the 0x0 case), effectively zeroing it out. Certain, compilers would * have done this for us automatically. */ output &= ((shift_amount > 31) - 1); /* If the input double was a negative number, then we have to negate our * output. The most straightforward way to do this would be: * * if (!top) * output = -output; * * as "top" at this point is either 0x0 (if the input was negative) or * 0xFFFFFFFF (if the input was positive). But, we can use a trick to * avoid the branch. Observe that the following snippet of code has the * same effect as the reference snippet above: * * if (!top) * output = 0 - output; * else * output = output - 0; * * Armed with the bitmask found in "top", we can condense the two statements * into the following: * * output = (output & top) - (output & ~top); * * where, in the case that the input double was negative, "top" will be 0, * and the statement will be equivalent to: * * output = (0) - (output); * * and if the input double was positive, "top" will be 0xFFFFFFFF, and the * statement will be equivalent to: * * output = (output) - (0); * * Which, as pointed out earlier, is equivalent to the original reference * snippet. */ output = (output & top) - (output & ~top); return output; #undef MSW #undef LSW } #ifdef _WIN32 #define WIN32_LEAN_AND_MEAN /* We require Windows 2000 features such as ETO_PDY */ #if !defined(WINVER) || (WINVER < 0x0500) # define WINVER 0x0500 #endif #if !defined(_WIN32_WINNT) || (_WIN32_WINNT < 0x0500) # define _WIN32_WINNT 0x0500 #endif #include <windows.h> #include <io.h> /* tmpfile() replacment for Windows. * * On Windows tmpfile() creates the file in the root directory. This * may fail due to unsufficient privileges. */ FILE * _cairo_win32_tmpfile (void) { DWORD path_len; WCHAR path_name[MAX_PATH + 1]; WCHAR file_name[MAX_PATH + 1]; HANDLE handle; int fd; FILE *fp; path_len = GetTempPathW (MAX_PATH, path_name); if (path_len <= 0 || path_len >= MAX_PATH) return NULL; if (GetTempFileNameW (path_name, L"ps_", 0, file_name) == 0) return NULL; handle = CreateFileW (file_name, GENERIC_READ | GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_DELETE_ON_CLOSE, NULL); if (handle == INVALID_HANDLE_VALUE) { DeleteFileW (file_name); return NULL; } fd = _open_osfhandle((intptr_t) handle, 0); if (fd < 0) { CloseHandle (handle); return NULL; } fp = fdopen(fd, "w+b"); if (fp == NULL) { _close(fd); return NULL; } return fp; } #endif /* _WIN32 */