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207062a996
pdfio/ttf.c
Michael R Sweet 207062a996
Add size limiting for num_cmap and nGlyphs.
2024-08-05 10:16:00 -04:00

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//
// Implementation file for TTF library
//
// https://github.com/michaelrsweet/ttf
//
// Copyright © 2018-2024 by Michael R Sweet.
//
// Licensed under Apache License v2.0. See the file "LICENSE" for more
// information.
//
#ifdef _WIN32
# define _CRT_SECURE_NO_WARNINGS
#endif // _WIN32
#include "ttf.h"
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <fcntl.h>
#ifdef _WIN32
# include <io.h>
# include <direct.h>
//
// Microsoft renames the POSIX functions to _name, and introduces
// a broken compatibility layer using the original names. As a result,
// random crashes can occur when, for example, strdup() allocates memory
// from a different heap than used by malloc() and free().
//
// To avoid moronic problems like this, we #define the POSIX function
// names to the corresponding non-standard Microsoft names.
//
# define access _access
# define close _close
# define fileno _fileno
# define lseek _lseek
# define mkdir(d,p) _mkdir(d)
# define open _open
# define read _read
# define rmdir _rmdir
# define snprintf _snprintf
# define strdup _strdup
# define unlink _unlink
# define vsnprintf _vsnprintf
# define write _write
//
// Map various parameters for POSIX...
//
# define F_OK 00
# define W_OK 02
# define R_OK 04
# define O_BINARY _O_BINARY
# define O_RDONLY _O_RDONLY
# define O_WRONLY _O_WRONLY
# define O_CREAT _O_CREAT
# define O_TRUNC _O_TRUNC
typedef __int64 ssize_t; // POSIX type not present on Windows...
#else
# include <unistd.h>
# define O_BINARY 0
#endif // _WIN32
//
// DEBUG is typically defined for debug builds. TTF_DEBUG maps to fprintf when
// DEBUG is defined and is a no-op otherwise...
//
#ifdef DEBUG
# define TTF_DEBUG(...) fprintf(stderr, __VA_ARGS__)
#else
# define TTF_DEBUG(...)
#endif // DEBUG
//
// TTF_FORMAT_ARGS tells the compiler to validate printf-style format
// arguments, producing warnings when there are issues...
//
#if defined(__has_extension) || defined(__GNUC__)
# define TTF_FORMAT_ARGS(a,b) __attribute__ ((__format__(__printf__, a, b)))
#else
# define TTF_FORMAT_ARGS(a,b)
#endif // __has_extension || __GNUC__
//
// Constants...
//
#define TTF_FONT_MAX_CHAR 262144 // Maximum number of character values
#define TTF_FONT_MAX_GROUPS 65536 // Maximum number of sub-groups
//
// TTF/OFF tag constants...
//
#define TTF_OFF_cmap 0x636d6170 // Character to glyph mapping
#define TTF_OFF_head 0x68656164 // Font header
#define TTF_OFF_hhea 0x68686561 // Horizontal header
#define TTF_OFF_hmtx 0x686d7478 // Horizontal metrics
#define TTF_OFF_maxp 0x6d617870 // Maximum profile
#define TTF_OFF_name 0x6e616d65 // Naming table
#define TTF_OFF_OS_2 0x4f532f32 // OS/2 and Windows specific metrics
#define TTF_OFF_post 0x706f7374 // PostScript information
#define TTF_OFF_Unicode 0 // Unicode platform ID
#define TTF_OFF_Mac 1 // Macintosh platform ID
#define TTF_OFF_Mac_Roman 0 // Macintosh Roman encoding ID
#define TTF_OFF_Mac_USEnglish 0 // Macintosh US English language ID
#define TTF_OFF_Windows 3 // Windows platform ID
#define TTF_OFF_Windows_English 9 // Windows English language ID base
#define TTF_OFF_Windows_UCS2 1 // Windows UCS-2 encoding
#define TTF_OFF_Windows_UCS4 10 // Windows UCS-4 encoding
#define TTF_OFF_Copyright 0 // Copyright naming string
#define TTF_OFF_FontFamily 1 // Font family naming string ("Arial")
#define TTF_OFF_FontSubfamily 2 // Font sub-family naming string ("Bold")
#define TTF_OFF_FontFullName 4 // Font full name ("Arial Bold")
#define TTF_OFF_FontVersion 5 // Font version number
#define TTF_OFF_PostScriptName 6 // Font PostScript name
//
// Local types...
//
typedef struct _ttf_metric_s //*** Font metric information ****/
{
short width, // Advance width
left_bearing; // Left side bearing
} _ttf_metric_t;
typedef struct _ttf_off_dir_s // OFF/TTF directory entry
{
unsigned tag; // Table identifier
unsigned checksum; // Checksum of table
unsigned offset; // Offset from the beginning of the file
unsigned length; // Length
} _ttf_off_dir_t;
typedef struct _ttf_off_table_s // OFF/TTF offset table
{
int num_entries; // Number of table entries
_ttf_off_dir_t *entries; // Table entries
} _ttf_off_table_t;
typedef struct _ttf_off_name_s // OFF/TTF name string
{
unsigned short platform_id, // Platform identifier
encoding_id, // Encoding identifier
language_id, // Language identifier
name_id, // Name identifier
length, // Length of string
offset; // Offset from start of storage area
} _ttf_off_name_t;
typedef struct _ttf_off_names_s // OFF/TTF naming table
{
int num_names; // Number of names
_ttf_off_name_t *names; // Names
unsigned char *storage; // Storage area
unsigned storage_size; // Size of storage area
} _ttf_off_names_t;
struct _ttf_s
{
int fd; // File descriptor
size_t idx; // Font number in file
ttf_err_cb_t err_cb; // Error callback, if any
void *err_data; // Error callback data
_ttf_off_table_t table; // Offset table
_ttf_off_names_t names; // Names
size_t num_fonts; // Number of fonts in this file
char *copyright; // Copyright string
char *family; // Font family string
char *postscript_name; // PostScript name string
char *version; // Font version string
bool is_fixed; // Is this a fixed-width font?
int max_char, // Last character in font
min_char; // First character in font
size_t num_cmap; // Number of entries in glyph map
int *cmap; // Unicode character to glyph map
_ttf_metric_t *widths[TTF_FONT_MAX_CHAR / 256];
// Character metrics (sparse array)
float units; // Width units
short ascent, // Maximum ascent above baseline
descent, // Maximum descent below baseline
cap_height, // "A" height
x_height, // "x" height
x_max, // Bounding box
x_min,
y_max,
y_min,
weight; // Font weight
float italic_angle; // Angle of italic text
ttf_stretch_t stretch; // Font stretch value
ttf_style_t style; // Font style
};
typedef struct _ttf_off_cmap4_s // Format 4 cmap table
{
unsigned short startCode, // First character
endCode, // Last character
idRangeOffset; // Offset for range (modulo 65536)
short idDelta; // Delta for range (modulo 65536)
} _ttf_off_cmap4_t;
typedef struct _ttf_off_cmap12_s // Format 12 cmap table
{
unsigned startCharCode, // First character
endCharCode, // Last character
startGlyphID; // Glyph index for the first character
} _ttf_off_cmap12_t;
typedef struct _ttf_off_cmap13_s // Format 13 cmap table
{
unsigned startCharCode, // First character
endCharCode, // Last character
glyphID; // Glyph index for all characters
} _ttf_off_cmap13_t;
typedef struct _ttf_off_head_s // Font header
{
unsigned short unitsPerEm; // Units for widths/coordinates
short xMin, // Bounding box of all glyphs
yMin,
xMax,
yMax;
unsigned short macStyle; // Mac style bits
} _ttf_off_head_t;
#define TTF_OFF_macStyle_Bold 0x01
#define TTF_OFF_macStyle_Italic 0x02
#define TTF_OFF_macStyle_Underline 0x04
#define TTF_OFF_macStyle_Outline 0x08
#define TTF_OFF_macStyle_Shadow 0x10
#define TTF_OFF_macStyle_Condensed 0x20
#define TTF_OFF_macStyle_Extended 0x40
typedef struct _ttf_off_hhea_s // Horizontal header
{
short ascender, // Ascender
descender; // Descender
int numberOfHMetrics; // Number of horizontal metrics
} _ttf_off_hhea_t;
typedef struct _ttf_off_os_2_s // OS/2 information
{
unsigned short usWeightClass, // Font weight
usWidthClass, // Font weight
fsType; // Type bits
short sTypoAscender, // Ascender
sTypoDescender, // Descender
sxHeight, // xHeight
sCapHeight; // CapHeight
} _ttf_off_os_2_t;
typedef struct _ttf_off_post_s // PostScript information
{
float italicAngle; // Italic angle
unsigned isFixedPitch; // Fixed-width font?
} _ttf_off_post_t;
//
// Local functions...
//
static char *copy_name(ttf_t *font, unsigned name_id);
static void errorf(ttf_t *font, const char *message, ...) TTF_FORMAT_ARGS(2,3);
static bool read_cmap(ttf_t *font);
static bool read_head(ttf_t *font, _ttf_off_head_t *head);
static bool read_hhea(ttf_t *font, _ttf_off_hhea_t *hhea);
static _ttf_metric_t *read_hmtx(ttf_t *font, _ttf_off_hhea_t *hhea);
static int read_maxp(ttf_t *font);
static bool read_names(ttf_t *font);
static bool read_os_2(ttf_t *font, _ttf_off_os_2_t *os_2);
static bool read_post(ttf_t *font, _ttf_off_post_t *post);
static int read_short(ttf_t *font);
static bool read_table(ttf_t *font);
static unsigned read_ulong(ttf_t *font);
static int read_ushort(ttf_t *font);
static unsigned seek_table(ttf_t *font, unsigned tag, unsigned offset, bool required);
//
// 'ttfCreate()' - Create a new font object for the named font family.
//
ttf_t * // O - New font object
ttfCreate(const char *filename, // I - Filename
size_t idx, // I - Font number to create in collection (0-based)
ttf_err_cb_t err_cb, // I - Error callback or `NULL` to log to stderr
void *err_data) // I - Error callback data
{
ttf_t *font = NULL; // New font object
size_t i; // Looping var
_ttf_metric_t *widths = NULL; // Glyph metrics
_ttf_off_head_t head; // head table
_ttf_off_hhea_t hhea; // hhea table
_ttf_off_os_2_t os_2; // OS/2 table
_ttf_off_post_t post; // PostScript table
TTF_DEBUG("ttfCreate(filename=\"%s\", idx=%u, err_cb=%p, err_data=%p)\n", filename, (unsigned)idx, err_cb, err_data);
// Range check input..
if (!filename)
{
errno = EINVAL;
return (NULL);
}
// Allocate memory...
if ((font = (ttf_t *)calloc(1, sizeof(ttf_t))) == NULL)
return (NULL);
font->idx = idx;
font->err_cb = err_cb;
font->err_data = err_data;
// Open the font file...
if ((font->fd = open(filename, O_RDONLY | O_BINARY)) < 0)
{
errorf(font, "Unable to open '%s': %s", filename, strerror(errno));
goto error;
}
TTF_DEBUG("ttfCreate: fd=%d\n", font->fd);
// Read the table of contents and the identifying names...
if (!read_table(font))
goto error;
TTF_DEBUG("ttfCreate: num_entries=%d\n", font->table.num_entries);
if (!read_names(font))
goto error;
TTF_DEBUG("ttfCreate: num_names=%d\n", font->names.num_names);
// Copy key font meta data strings...
font->copyright = copy_name(font, TTF_OFF_Copyright);
font->family = copy_name(font, TTF_OFF_FontFamily);
font->postscript_name = copy_name(font, TTF_OFF_PostScriptName);
font->version = copy_name(font, TTF_OFF_FontVersion);
if (read_post(font, &post))
{
font->italic_angle = post.italicAngle;
font->is_fixed = post.isFixedPitch != 0;
}
TTF_DEBUG("ttfCreate: copyright=\"%s\"\n", font->copyright);
TTF_DEBUG("ttfCreate: family=\"%s\"\n", font->family);
TTF_DEBUG("ttfCreate: postscript_name=\"%s\"\n", font->postscript_name);
TTF_DEBUG("ttfCreate: version=\"%s\"\n", font->version);
TTF_DEBUG("ttfCreate: italic_angle=%g\n", font->italic_angle);
TTF_DEBUG("ttfCreate: is_fixed=%s\n", font->is_fixed ? "true" : "false");
if (!read_cmap(font))
goto error;
if (!read_head(font, &head))
goto error;
font->units = (float)head.unitsPerEm;
font->x_max = head.xMax;
font->x_min = head.xMin;
font->y_max = head.yMax;
font->y_min = head.yMin;
if (head.macStyle & TTF_OFF_macStyle_Italic)
{
if (font->postscript_name && strstr(font->postscript_name, "Oblique"))
font->style = TTF_STYLE_OBLIQUE;
else
font->style = TTF_STYLE_ITALIC;
}
else
font->style = TTF_STYLE_NORMAL;
if (!read_hhea(font, &hhea))
goto error;
font->ascent = hhea.ascender;
font->descent = hhea.descender;
if (read_maxp(font) < 0)
goto error;
if (hhea.numberOfHMetrics > 0)
{
if ((widths = read_hmtx(font, &hhea)) == NULL)
goto error;
}
else
{
errorf(font, "Number of horizontal metrics is 0.");
goto error;
}
if (read_os_2(font, &os_2))
{
// Copy key values from OS/2 table...
static const ttf_stretch_t stretches[] =
{
TTF_STRETCH_ULTRA_CONDENSED, // ultra-condensed
TTF_STRETCH_EXTRA_CONDENSED, // extra-condensed
TTF_STRETCH_CONDENSED, // condensed
TTF_STRETCH_SEMI_CONDENSED, // semi-condensed
TTF_STRETCH_NORMAL, // normal
TTF_STRETCH_SEMI_EXPANDED, // semi-expanded
TTF_STRETCH_EXPANDED, // expanded
TTF_STRETCH_EXTRA_EXPANDED, // extra-expanded
TTF_STRETCH_ULTRA_EXPANDED // ultra-expanded
};
if (os_2.usWidthClass >= 1 && os_2.usWidthClass <= (int)(sizeof(stretches) / sizeof(stretches[0])))
font->stretch = stretches[os_2.usWidthClass - 1];
font->weight = (short)os_2.usWeightClass;
font->cap_height = os_2.sCapHeight;
font->x_height = os_2.sxHeight;
}
else
{
// Default key values since there isn't an OS/2 table...
TTF_DEBUG("ttfCreate: Unable to read OS/2 table.\n");
font->weight = 400;
}
if (font->cap_height == 0)
font->cap_height = font->ascent;
if (font->x_height == 0)
font->x_height = 3 * font->ascent / 5;
// Build a sparse glyph widths table...
font->min_char = -1;
for (i = 0; i < font->num_cmap; i ++)
{
if (font->cmap[i] >= 0)
{
int bin = (int)i / 256, // Sub-array bin
glyph = font->cmap[i]; // Glyph index
// Update min/max...
if (font->min_char < 0)
font->min_char = (int)i;
font->max_char = (int)i;
// Allocate a sub-array as needed...
if (!font->widths[bin])
font->widths[bin] = (_ttf_metric_t *)calloc(256, sizeof(_ttf_metric_t));
// Copy the width of the specified glyph or the last one if we are past
// the end of the table...
if (glyph >= hhea.numberOfHMetrics)
font->widths[bin][i & 255] = widths[hhea.numberOfHMetrics - 1];
else
font->widths[bin][i & 255] = widths[glyph];
}
#ifdef DEBUG
if (i >= ' ' && i < 127 && font->widths[0])
TTF_DEBUG("ttfCreate: width['%c']=%d(%d)\n", (char)i, font->widths[0][i].width, font->widths[0][i].left_bearing);
#endif // DEBUG
}
// Cleanup and return the font...
free(widths);
return (font);
// If we get here something bad happened...
error:
free(widths);
ttfDelete(font);
return (NULL);
}
//
// 'ttfDelete()' - Free all memory used for a font family object.
//
void
ttfDelete(ttf_t *font) // I - Font
{
int i; // Looping var
// Range check input...
if (!font)
return;
// Close the font file...
if (font->fd >= 0)
close(font->fd);
// Free all memory used...
free(font->copyright);
free(font->family);
free(font->postscript_name);
free(font->version);
free(font->table.entries);
free(font->names.names);
free(font->names.storage);
free(font->cmap);
for (i = 0; i < 256; i ++)
free(font->widths[i]);
free(font);
}
//
// 'ttfGetAscent()' - Get the maximum height of non-accented characters.
//
int // O - Ascent in 1000ths
ttfGetAscent(ttf_t *font) // I - Font
{
return (font ? (int)(1000 * font->ascent / font->units) : 0);
}
//
// 'ttfGetBounds()' - Get the bounds of all characters in a font.
//
ttf_rect_t * // O - Bounds or `NULL` on error
ttfGetBounds(ttf_t *font, // I - Font
ttf_rect_t *bounds) // I - Bounds buffer
{
// Range check input...
if (!font || !bounds)
{
if (bounds)
memset(bounds, 0, sizeof(ttf_rect_t));
return (NULL);
}
bounds->left = 1000.0f * font->x_min / font->units;
bounds->right = 1000.0f * font->x_max / font->units;
bounds->bottom = 1000.0f * font->y_min / font->units;
bounds->top = 1000.0f * font->y_max / font->units;
return (bounds);
}
//
// 'ttfGetCapHeight()' - Get the height of capital letters.
//
int // O - Capital letter height in 1000ths
ttfGetCapHeight(ttf_t *font) // I - Font
{
return (font ? (int)(1000 * font->cap_height / font->units) : 0);
}
//
// 'ttfGetCMap()' - Get the Unicode to glyph mapping table.
//
const int * // O - CMap table
ttfGetCMap(ttf_t *font, // I - Font
size_t *num_cmap) // O - Number of entries in table
{
// Range check input...
if (!font || !num_cmap)
{
if (num_cmap)
*num_cmap = 0;
return (NULL);
}
*num_cmap = font->num_cmap;
return (font->cmap);
}
//
// 'ttfGetCopyright()' - Get the copyright text for a font.
//
const char * // O - Copyright text
ttfGetCopyright(ttf_t *font) // I - Font
{
return (font ? font->copyright : NULL);
}
//
// 'ttfGetDescent()' - Get the maximum depth of non-accented characters.
//
int // O - Descent in 1000ths
ttfGetDescent(ttf_t *font) // I - Font
{
return (font ? (int)(1000 * font->descent / font->units) : 0);
}
//
// 'ttfGetExtents()' - Get the extents of a UTF-8 string.
//
// This function computes the extents of a UTF-8 string when rendered using the
// specified font and size.
//
ttf_rect_t * // O - Pointer to extents or `NULL` on error
ttfGetExtents(
ttf_t *font, // I - Font
float size, // I - Font size
const char *s, // I - String
ttf_rect_t *extents) // O - Extents of the string
{
bool first = true; // First character?
int ch, // Current character
width = 0; // Width
_ttf_metric_t *widths; // Widths
TTF_DEBUG("ttfGetExtents(font=%p, size=%.2f, s=\"%s\", extents=%p)\n", (void *)font, size, s, (void *)extents);
// Make sure extents is zeroed out...
if (extents)
memset(extents, 0, sizeof(ttf_rect_t));
// Range check input...
if (!font || size <= 0.0f || !s || !extents)
return (NULL);
// Loop through the string...
while (*s)
{
// Get the next Unicode character...
if ((*s & 0xe0) == 0xc0 && (s[1] & 0xc0) == 0x80)
{
// Two byte UTF-8
ch = ((*s & 0x1f) << 6) | (s[1] & 0x3f);
s += 2;
}
else if ((*s & 0xf0) == 0xe0 && (s[1] & 0xc0) == 0x80 && (s[2] & 0xc0) == 0x80)
{
// Three byte UTF-8
ch = ((*s & 0x0f) << 12) | ((s[1] & 0x3f) << 6) | (s[2] & 0x3f);
s += 3;
}
else if ((*s & 0xf8) == 0xf0 && (s[1] & 0xc0) == 0x80 && (s[2] & 0xc0) == 0x80 && (s[3] & 0xc0) == 0x80)
{
// Four byte UTF-8
ch = ((*s & 0x07) << 18) | ((s[1] & 0x3f) << 12) | ((s[2] & 0x3f) << 6) | (s[3] & 0x3f);
s += 4;
}
else if (*s & 0x80)
{
// Invalid UTF-8
errorf(font, "Invalid UTF-8 sequence starting with 0x%02X.", *s & 255);
return (NULL);
}
else
{
// ASCII...
ch = *s++;
}
// Find its width...
if ((widths = font->widths[ch / 256]) != NULL)
{
if (first)
{
extents->left = -widths[ch & 255].left_bearing / font->units;
first = false;
}
width += widths[ch & 255].width;
}
else if ((widths = font->widths[0]) != NULL)
{
// Use the ".notdef" (0) glyph width...
if (first)
{
extents->left = -widths[0].left_bearing / font->units;
first = false;
}
width += widths[0].width;
}
}
// Calculate the bounding box for the text and return...
TTF_DEBUG("ttfGetExtents: width=%d\n", width);
extents->bottom = size * font->y_min / font->units;
extents->right = size * width / font->units + extents->left;
extents->top = size * font->y_max / font->units;
return (extents);
}
//
// 'ttfGetFamily()' - Get the family name of a font.
//
const char * // O - Family name
ttfGetFamily(ttf_t *font) // I - Font
{
return (font ? font->family : NULL);
}
//
// 'ttfGetItalicAngle()' - Get the italic angle.
//
float // O - Angle in degrees
ttfGetItalicAngle(ttf_t *font) // I - Font
{
return (font ? font->italic_angle : 0.0f);
}
//
// 'ttfGetMaxChar()' - Get the last character in the font.
//
int // O - Last character in font
ttfGetMaxChar(ttf_t *font) // I - Font
{
return (font ? font->max_char : 0);
}
//
// 'ttfGetMinChar()' - Get the first character in the font.
//
int // O - First character in font
ttfGetMinChar(ttf_t *font) // I - Font
{
return (font ? font->min_char : 0);
}
//
// 'ttfGetNumFonts()' - Get the number of fonts in this collection.
//
size_t // O - Number of fonts
ttfGetNumFonts(ttf_t *font) // I - Font
{
return (font ? font->num_fonts : 0);
}
//
// 'ttfGetPostScriptName()' - Get the PostScript name of a font.
//
const char * // O - PostScript name
ttfGetPostScriptName(
ttf_t *font) // I - Font
{
return (font ? font->postscript_name : NULL);
}
//
// 'ttfGetStretch()' - Get the font "stretch" value...
//
ttf_stretch_t // O - Stretch value
ttfGetStretch(ttf_t *font) // I - Font
{
return (font ? font->stretch : TTF_STRETCH_NORMAL);
}
//
// 'ttfGetStyle()' - Get the font style.
//
ttf_style_t // O - Style
ttfGetStyle(ttf_t *font) // I - Font
{
return (font ? font->style : TTF_STYLE_NORMAL);
}
//
// 'ttfGetVersion()' - Get the version number of a font.
//
const char * // O - Version number
ttfGetVersion(ttf_t *font) // I - Font
{
return (font ? font->version : NULL);
}
//
// 'ttfGetWeight()' - Get the weight of a font.
//
ttf_weight_t // O - Weight
ttfGetWeight(ttf_t *font) // I - Font
{
return (font ? (ttf_weight_t)font->weight : TTF_WEIGHT_400);
}
//
// 'ttfGetWidth()' - Get the width of a single character.
//
int // O - Width in 1000ths
ttfGetWidth(ttf_t *font, // I - Font
int ch) // I - Unicode character
{
int bin = ch >> 8; // Bin in widths array
// Range check input...
if (!font || ch < ' ' || ch == 0x7f)
return (0);
if (font->widths[bin])
return ((int)(1000.0f * font->widths[bin][ch & 255].width / font->units));
else if (font->widths[0]) // .notdef
return ((int)(1000.0f * font->widths[0][0].width / font->units));
else
return (0);
}
//
// 'ttfGetXHeight()' - Get the height of lowercase letters.
//
int // O - Lowercase letter height in 1000ths
ttfGetXHeight(ttf_t *font) // I - Font
{
return (font ? (int)(1000 * font->x_height / font->units) : 0);
}
//
// 'ttfIsFixedPitch()' - Determine whether a font is fixedpitch.
//
bool // O - `true` if fixed pitch, `false` otherwise
ttfIsFixedPitch(ttf_t *font) // I - Font
{
return (font ? font->is_fixed : false);
}
//
// 'copy_name()' - Copy a name string from a font.
//
static char * // O - Name string or `NULL`
copy_name(ttf_t *font, // I - Font
unsigned name_id) // I - Name identifier
{
int i; // Looping var
_ttf_off_name_t *name; // Current name
for (i = font->names.num_names, name = font->names.names; i > 0; i --, name ++)
{
if (name->name_id == name_id &&
((name->platform_id == TTF_OFF_Mac && name->language_id == TTF_OFF_Mac_USEnglish) ||
(name->platform_id == TTF_OFF_Windows && (name->language_id & 0xff) == TTF_OFF_Windows_English)))
{
char temp[1024], // Temporary string buffer
*tempptr, // Pointer into temporary string
*storptr; // Pointer into storage
int chars, // Length of string to copy in characters
bpc; // Bytes per character
if ((unsigned)(name->offset + name->length) > font->names.storage_size)
{
TTF_DEBUG("copy_name: offset(%d)+length(%d) > storage_size(%d)\n", name->offset, name->length, font->names.storage_size);
continue;
}
if (name->platform_id == TTF_OFF_Windows && name->encoding_id == TTF_OFF_Windows_UCS2)
{
storptr = (char *)font->names.storage + name->offset;
chars = name->length / 2;
bpc = 2;
}
else if (name->platform_id == TTF_OFF_Windows && name->encoding_id == TTF_OFF_Windows_UCS4)
{
storptr = (char *)font->names.storage + name->offset;
chars = name->length / 4;
bpc = 4;
}
else
{
storptr = (char *)font->names.storage + name->offset;
chars = name->length;
bpc = 1;
}
for (tempptr = temp; chars > 0; storptr += bpc, chars --)
{
int ch; // Current character
// Convert to Unicode...
if (bpc == 1)
ch = *storptr;
else if (bpc == 2)
ch = ((storptr[0] & 255) << 8) | (storptr[1] & 255);
else
ch = ((storptr[0] & 255) << 24) | ((storptr[1] & 255) << 16) | ((storptr[2] & 255) << 8) | (storptr[3] & 255);
// Convert to UTF-8...
if (ch < 0x80)
{
// ASCII...
if (tempptr < (temp + sizeof(temp) - 1))
*tempptr++ = (char)ch;
else
break;
}
else if (ch < 0x400)
{
// Two byte UTF-8
if (tempptr < (temp + sizeof(temp) - 2))
{
*tempptr++ = (char)(0xc0 | (ch >> 6));
*tempptr++ = (char)(0x80 | (ch & 0x3f));
}
else
break;
}
else if (ch < 0x10000)
{
// Three byte UTF-8
if (tempptr < (temp + sizeof(temp) - 3))
{
*tempptr++ = (char)(0xe0 | (ch >> 12));
*tempptr++ = (char)(0x80 | ((ch >> 6) & 0x3f));
*tempptr++ = (char)(0x80 | (ch & 0x3f));
}
else
break;
}
else
{
// Four byte UTF-8
if (tempptr < (temp + sizeof(temp) - 4))
{
*tempptr++ = (char)(0xf0 | (ch >> 18));
*tempptr++ = (char)(0x80 | ((ch >> 12) & 0x3f));
*tempptr++ = (char)(0x80 | ((ch >> 6) & 0x3f));
*tempptr++ = (char)(0x80 | (ch & 0x3f));
}
else
break;
}
}
*tempptr = '\0';
TTF_DEBUG("copy_name: name_id(%d) = \"%s\"\n", name_id, temp);
return (strdup(temp));
}
}
TTF_DEBUG("copy_name: No English name string for %d.\n", name_id);
#ifdef DEBUG
for (i = font->names.num_names, name = font->names.names; i > 0; i --, name ++)
{
if (name->name_id == name_id)
TTF_DEBUG("copy_name: Found name_id=%d, platform_id=%d, language_id=%d(0x%04x)\n", name_id, name->platform_id, name->language_id, name->language_id);
}
#endif // DEBUG
return (NULL);
}
//
// 'errorf()' - Show an error message.
//
static void
errorf(ttf_t *font, // I - Font
const char *message, // I - `printf`-style message string
...) // I - Addition arguments as needed
{
va_list ap; // Argument pointer
char buffer[2048]; // Message buffer
// Format the message...
va_start(ap, message);
vsnprintf(buffer, sizeof(buffer), message, ap);
va_end(ap);
// If an error callback is set, sent the message there. Otherwise write it
// to stderr...
if (font && font->err_cb)
(font->err_cb)(font->err_data, buffer);
else
fprintf(stderr, "%s\n", message);
}
/*
* 'read_cmap()' - Read the cmap table, getting the Unicode mapping table.
*/
static bool // O - `true` on success, `false` on error
read_cmap(ttf_t *font) // I - Font
{
unsigned length; // Length of cmap table
int i, // Looping var
temp, // Temporary value
num_tables, // Number of cmap tables
platform_id, // Platform identifier (Windows or Mac)
encoding_id, // Encoding identifier (varies)
cformat; // Formap of cmap data
unsigned clength, // Length of cmap data
coffset = 0, // Offset to cmap data
roman_offset = 0; // MacRoman offset
int *cmapptr; // Pointer into cmap
#if 0
const int *unimap = NULL; // Unicode character map, if any
static const int romanmap[256] = // MacRoman to Unicode map
{
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F,
0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0x3E, 0x3F,
0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F,
0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
0x58, 0x59, 0x5A, 0x5B, 0x5C, 0x5D, 0x5E, 0x5F,
0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F,
0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F,
0xC4, 0xC5, 0xC7, 0xC9, 0xD1, 0xD6, 0xDC, 0xE1,
0xE0, 0xE2, 0xE4, 0xE3, 0xE5, 0xE7, 0xE9, 0xE8,
0xEA, 0xEB, 0xED, 0xEC, 0xEE, 0xEF, 0xF1, 0xF3,
0xF2, 0xF4, 0xF6, 0xF5, 0xFA, 0xF9, 0xFB, 0xFC,
0x2020, 0xB0, 0xA2, 0xA3, 0xA7, 0x2022, 0xB6, 0xDF,
0xAE, 0xA9, 0x2122, 0xB4, 0xA8, 0x2260, 0xC6, 0xD8,
0x221E, 0xB1, 0x2264, 0x2265, 0xA5, 0xB5, 0x2202, 0x2211,
0x220F, 0x3C0, 0x222B, 0xAA, 0xBA, 0x3A9, 0xE6, 0xF8,
0xBF, 0xA1, 0xAC, 0x221A, 0x192, 0x2248, 0x2206, 0xAB,
0xBB, 0x2026, 0xA0, 0xC0, 0xC3, 0xD5, 0x152, 0x153,
0x2013, 0x2014, 0x201C, 0x201D, 0x2018, 0x2019, 0xF7, 0x25CA,
0xFF, 0x178, 0x2044, 0x20AC, 0x2039, 0x203A, 0xFB01, 0xFB02,
0x2021, 0xB7, 0x201A, 0x201E, 0x2030, 0xC2, 0xCA, 0xC1,
0xCB, 0xC8, 0xCD, 0xCE, 0xCF, 0xCC, 0xD3, 0xD4,
0xF8FF, 0xD2, 0xDA, 0xDB, 0xD9, 0x131, 0x2C6, 0x2DC,
0xAF, 0x2D8, 0x2D9, 0x2DA, 0xB8, 0x2DD, 0x2DB, 0x2C7
};
#endif /* 0 */
// Find the cmap table...
if (seek_table(font, TTF_OFF_cmap, 0, true) == 0)
return (false);
if ((temp = read_ushort(font)) != 0)
{
errorf(font, "Unknown cmap version %d.", temp);
return (false);
}
if ((num_tables = read_ushort(font)) < 1)
{
errorf(font, "No cmap tables to read.");
return (false);
}
TTF_DEBUG("read_cmap: num_tables=%d\n", num_tables);
// Find a Unicode table we can use...
for (i = 0; i < num_tables; i ++)
{
platform_id = read_ushort(font);
encoding_id = read_ushort(font);
coffset = read_ulong(font);
TTF_DEBUG("read_cmap: table[%d].platform_id=%d, encoding_id=%d, coffset=%u\n", i, platform_id, encoding_id, coffset);
if (platform_id == TTF_OFF_Unicode || (platform_id == TTF_OFF_Windows && encoding_id == TTF_OFF_Windows_UCS2))
break;
if (platform_id == TTF_OFF_Mac && encoding_id == TTF_OFF_Mac_Roman)
roman_offset = coffset;
}
if (i >= num_tables)
{
if (roman_offset)
{
TTF_DEBUG("read_cmap: Using MacRoman cmap table.\n");
coffset = roman_offset;
}
else
{
errorf(font, "No usable cmap table.");
return (false);
}
}
if ((length = seek_table(font, TTF_OFF_cmap, coffset, true)) == 0)
return (false);
if ((cformat = read_ushort(font)) < 0)
{
errorf(font, "Unable to read cmap table format at offset %u.", coffset);
return (false);
}
TTF_DEBUG("read_cmap: cformat=%d\n", cformat);
switch (cformat)
{
case 0 :
{
// Format 0: Byte encoding table.
//
// This is a simple 8-bit mapping.
size_t j; // Looping var
unsigned char bmap[256]; // Byte map buffer
if ((unsigned)read_ushort(font) == (unsigned)-1)
{
errorf(font, "Unable to read cmap table length at offset %u.", coffset);
return (false);
}
/* language = */ read_ushort(font);
if (length > (256 + 6))
{
errorf(font, "Bad cmap table length at offset %u.", coffset);
return (false);
}
font->num_cmap = length - 6;
if ((font->cmap = (int *)malloc(font->num_cmap * sizeof(int))) == NULL)
{
errorf(font, "Unable to allocate cmap table.");
return (false);
}
if (read(font->fd, bmap, font->num_cmap) != (ssize_t)font->num_cmap)
{
errorf(font, "Unable to read cmap table length at offset %u.", coffset);
return (false);
}
// Copy into the actual cmap table...
for (j = 0; j < font->num_cmap; j ++)
font->cmap[j] = bmap[j];
}
break;
case 4 :
{
// Format 4: Segment mapping to delta values.
//
// This is an overly complicated linear way of encoding a sparse
// mapping table. And it uses 1-based indexing with modulo
// arithmetic...
int ch, // Current character
seg, // Current segment
glyph, // Current glyph
segCount, // Number of segments
numGlyphIdArray,// Number of glyph IDs
*glyphIdArray; // Glyph IDs
_ttf_off_cmap4_t *segments, // Segment data
*segment; // This segment
// Read the table...
if ((clength = (unsigned)read_ushort(font)) == (unsigned)-1)
{
errorf(font, "Unable to read cmap table length at offset %u.", coffset);
return (false);
}
TTF_DEBUG("read_cmap: clength=%u\n", clength);
/* language = */ read_ushort(font);
segCount = read_ushort(font) / 2;
/* searchRange = */ read_ushort(font);
/* entrySelectoed = */ read_ushort(font);
/* rangeShift = */ read_ushort(font);
TTF_DEBUG("read_cmap: segCount=%d\n", segCount);
if (segCount < 2)
{
errorf(font, "Bad cmap table.");
return (false);
}
numGlyphIdArray = ((int)clength - 8 * segCount - 16) / 2;
segments = (_ttf_off_cmap4_t *)calloc((size_t)segCount, sizeof(_ttf_off_cmap4_t));
glyphIdArray = (int *)calloc((size_t)numGlyphIdArray, sizeof(int));
if (!segments || !glyphIdArray)
{
errorf(font, "Unable to allocate memory for cmap.");
free(segments);
free(glyphIdArray);
return (false);
}
TTF_DEBUG("read_cmap: numGlyphIdArray=%d\n", numGlyphIdArray);
for (i = 0; i < segCount; i ++)
segments[i].endCode = (unsigned short)read_ushort(font);
/* reservedPad = */ read_ushort(font);
for (i = 0; i < segCount; i ++)
segments[i].startCode = (unsigned short)read_ushort(font);
for (i = 0; i < segCount; i ++)
segments[i].idDelta = (short)read_short(font);
for (i = 0; i < segCount; i ++)
segments[i].idRangeOffset = (unsigned short)read_ushort(font);
for (i = 0; i < numGlyphIdArray; i ++)
glyphIdArray[i] = read_ushort(font);
#ifdef DEBUG
for (i = 0; i < segCount; i ++)
TTF_DEBUG("read_cmap: segment[%d].startCode=%d, endCode=%d, idDelta=%d, idRangeOffset=%d\n", i, segments[i].startCode, segments[i].endCode, segments[i].idDelta, segments[i].idRangeOffset);
for (i = 0; i < numGlyphIdArray; i ++)
TTF_DEBUG("read_cmap: glyphIdArray[%d]=%d\n", i, glyphIdArray[i]);
#endif /* DEBUG */
// Based on the end code of the segent table, allocate space for the
// uncompressed cmap table...
// segCount --; // Last segment is not used (sigh)
font->num_cmap = segments[segCount - 1].endCode + 1;
if (font->num_cmap > TTF_FONT_MAX_CHAR)
{
errorf(font, "Invalid cmap table with %u characters.", (unsigned)font->num_cmap);
return (false);
}
font->cmap = cmapptr = (int *)malloc(font->num_cmap * sizeof(int));
if (!font->cmap)
{
errorf(font, "Unable to allocate memory for cmap.");
free(segments);
free(glyphIdArray);
return (false);
}
memset(cmapptr, -1, font->num_cmap * sizeof(int));
// Now loop through the segments and assign glyph indices from the
// array...
for (seg = segCount, segment = segments; seg > 0; seg --, segment ++)
{
for (ch = segment->startCode; ch <= segment->endCode; ch ++)
{
if (segment->idRangeOffset)
{
// Use an "obscure indexing trick" (words from the spec, not
// mine) to look up the glyph index...
temp = (int)(segment->idRangeOffset / 2 - segCount + (ch - segment->startCode) + (segment - segments));
TTF_DEBUG("read_cmap: ch=%d, temp=%d\n", ch, temp);
if (temp < 0 || temp >= numGlyphIdArray)
glyph = -1;
else
glyph = (glyphIdArray[temp] + segment->idDelta) & 65535;
}
else
{
// Just use idDelta to compute a glyph index...
glyph = (ch + segment->idDelta) & 65535;
}
cmapptr[ch] = glyph;
}
}
// Free the segment data...
free(segments);
free(glyphIdArray);
}
break;
case 12 :
{
// Format 12: Segmented coverage
//
// A simple sparse linear segment mapping format.
unsigned ch, // Current character
gidx, // Current group
nGroups; // Number of groups
_ttf_off_cmap12_t *groups, // Groups
*group; // This group
// Read the table...
/* reserved */ read_ushort(font);
if (read_ulong(font) == 0)
{
errorf(font, "Unable to read cmap table length at offset %u.", coffset);
return (false);
}
/* language = */ read_ulong(font);
nGroups = read_ulong(font);
TTF_DEBUG("read_cmap: nGroups=%u\n", nGroups);
if (nGroups > TTF_FONT_MAX_GROUPS)
{
errorf(font, "Invalid cmap table with %u groups.", nGroups);
return (false);
}
if ((groups = (_ttf_off_cmap12_t *)calloc(nGroups, sizeof(_ttf_off_cmap12_t))) == NULL)
{
errorf(font, "Unable to allocate memory for cmap.");
return (false);
}
for (gidx = 0, group = groups, font->num_cmap = 0; gidx < nGroups; gidx ++, group ++)
{
group->startCharCode = read_ulong(font);
group->endCharCode = read_ulong(font);
group->startGlyphID = read_ulong(font);
TTF_DEBUG("read_cmap: [%u] startCharCode=%u, endCharCode=%u, startGlyphID=%u\n", gidx, group->startCharCode, group->endCharCode, group->startGlyphID);
if (group->endCharCode >= font->num_cmap)
font->num_cmap = group->endCharCode + 1;
}
// Based on the end code of the segent table, allocate space for the
// uncompressed cmap table...
TTF_DEBUG("read_cmap: num_cmap=%u\n", (unsigned)font->num_cmap);
if (font->num_cmap > TTF_FONT_MAX_CHAR)
{
errorf(font, "Invalid cmap table with %u characters.", (unsigned)font->num_cmap);
return (false);
}
font->cmap = cmapptr = (int *)malloc(font->num_cmap * sizeof(int));
if (!font->cmap)
{
errorf(font, "Unable to allocate memory for cmap.");
free(groups);
return (false);
}
memset(cmapptr, -1, font->num_cmap * sizeof(int));
// Now loop through the groups and assign glyph indices from the
// array...
for (gidx = 0, group = groups; gidx < nGroups; gidx ++, group ++)
{
for (ch = group->startCharCode; ch <= group->endCharCode && ch < TTF_FONT_MAX_CHAR; ch ++)
cmapptr[ch] = (int)(group->startGlyphID + ch - group->startCharCode);
}
// Free the group data...
free(groups);
}
break;
case 13 :
{
// Format 13: Many-to-one range mappings
//
// Typically used for fonts of last resort where multiple characters
// map to the same glyph.
unsigned ch, // Current character
gidx, // Current group
nGroups; // Number of groups
_ttf_off_cmap13_t *groups, // Groups
*group; // This group
// Read the table...
/* reserved */ read_ushort(font);
if (read_ulong(font) == 0)
{
errorf(font, "Unable to read cmap table length at offset %u.", coffset);
return (false);
}
/* language = */ read_ulong(font);
nGroups = read_ulong(font);
TTF_DEBUG("read_cmap: nGroups=%u\n", nGroups);
if (nGroups > TTF_FONT_MAX_GROUPS)
{
errorf(font, "Invalid cmap table with %u groups.", nGroups);
return (false);
}
if ((groups = (_ttf_off_cmap13_t *)calloc(nGroups, sizeof(_ttf_off_cmap13_t))) == NULL)
{
errorf(font, "Unable to allocate memory for cmap.");
return (false);
}
for (gidx = 0, group = groups, font->num_cmap = 0; gidx < nGroups; gidx ++, group ++)
{
group->startCharCode = read_ulong(font);
group->endCharCode = read_ulong(font);
group->glyphID = read_ulong(font);
TTF_DEBUG("read_cmap: [%u] startCharCode=%u, endCharCode=%u, glyphID=%u\n", gidx, group->startCharCode, group->endCharCode, group->glyphID);
if (group->endCharCode >= font->num_cmap)
font->num_cmap = group->endCharCode + 1;
}
// Based on the end code of the segent table, allocate space for the
// uncompressed cmap table...
TTF_DEBUG("read_cmap: num_cmap=%u\n", (unsigned)font->num_cmap);
if (font->num_cmap > TTF_FONT_MAX_CHAR)
{
errorf(font, "Invalid cmap table with %u characters.", (unsigned)font->num_cmap);
return (false);
}
font->cmap = cmapptr = (int *)malloc(font->num_cmap * sizeof(int));
if (!font->cmap)
{
errorf(font, "Unable to allocate cmap.");
free(groups);
return (false);
}
memset(cmapptr, -1, font->num_cmap * sizeof(int));
// Now loop through the groups and assign glyph indices from the
// array...
for (gidx = 0, group = groups; gidx < nGroups; gidx ++, group ++)
{
for (ch = group->startCharCode; ch <= group->endCharCode && ch < TTF_FONT_MAX_CHAR; ch ++)
cmapptr[ch] = (int)group->glyphID;
}
// Free the group data...
free(groups);
}
break;
default :
errorf(font, "Format %d cmap tables are not yet supported.", cformat);
return (false);
}
#ifdef DEBUG
cmapptr = font->cmap;
for (i = 0; i < (int)font->num_cmap && i < 127; i ++)
{
if (cmapptr[i] >= 0)
TTF_DEBUG("read_cmap; cmap[%d]=%d\n", i, cmapptr[i]);
}
#endif // DEBUG
return (true);
}
//
// 'read_head()' - Read the head table.
//
static bool // O - `true` on success, `false` on error
read_head(ttf_t *font, // I - Font
_ttf_off_head_t *head) // O - head table data
{
memset(head, 0, sizeof(_ttf_off_head_t));
if (seek_table(font, TTF_OFF_head, 0, true) == 0)
return (false);
/* majorVersion */ read_ushort(font);
/* minorVersion */ read_ushort(font);
/* fontRevision */ read_ulong(font);
/* checkSumAdjustment */ read_ulong(font);
/* magicNumber */ read_ulong(font);
/* flags */ read_ushort(font);
head->unitsPerEm = (unsigned short)read_ushort(font);
/* created */ read_ulong(font); read_ulong(font);
/* modified */ read_ulong(font); read_ulong(font);
head->xMin = (short)read_short(font);
head->yMin = (short)read_short(font);
head->xMax = (short)read_short(font);
head->yMax = (short)read_short(font);
head->macStyle = (unsigned short)read_ushort(font);
return (true);
}
//
// 'read_hhea()' - Read the hhea table.
//
static bool // O - `true` on success, `false` on error
read_hhea(ttf_t *font, // I - Font
_ttf_off_hhea_t *hhea) // O - hhea table data
{
memset(hhea, 0, sizeof(_ttf_off_hhea_t));
if (seek_table(font, TTF_OFF_hhea, 0, true) == 0)
return (false);
/* majorVersion */ read_ushort(font);
/* minorVersion */ read_ushort(font);
hhea->ascender = (short)read_short(font);
hhea->descender = (short)read_short(font);
/* lineGap */ read_short(font);
/* advanceWidthMax */ read_ushort(font);
/* minLeftSideBearing */ read_short(font);
/* minRightSideBearing */ read_short(font);
/* mMaxExtent */ read_short(font);
/* caretSlopeRise */ read_short(font);
/* caretSlopeRun */ read_short(font);
/* caretOffset */ read_short(font);
/* (reserved) */ read_short(font);
/* (reserved) */ read_short(font);
/* (reserved) */ read_short(font);
/* (reserved) */ read_short(font);
/* metricDataFormat */ read_short(font);
hhea->numberOfHMetrics = (unsigned short)read_ushort(font);
return (true);
}
/*
* 'read_hmtx()' - Read the horizontal metrics from the font.
*/
static _ttf_metric_t * // O - Array of glyph metrics
read_hmtx(ttf_t *font, // I - Font
_ttf_off_hhea_t *hhea) // O - hhea table data
{
unsigned length; // Length of hmtx table
int i; // Looping var
_ttf_metric_t *widths; // Glyph metrics array
if ((length = seek_table(font, TTF_OFF_hmtx, 0, true)) == 0)
return (NULL);
if (length < (unsigned)(4 * hhea->numberOfHMetrics))
{
errorf(font, "Length of hhea table is only %u, expected at least %d.", length, 4 * hhea->numberOfHMetrics);
return (NULL);
}
if ((widths = (_ttf_metric_t *)calloc((size_t)hhea->numberOfHMetrics, sizeof(_ttf_metric_t))) == NULL)
return (NULL);
for (i = 0; i < hhea->numberOfHMetrics; i ++)
{
widths[i].width = (short)read_ushort(font);
widths[i].left_bearing = (short)read_short(font);
TTF_DEBUG("read_hmtx: widths[%d].width=%d, .left_bearing=%d\n", i, widths[i].width, widths[i].left_bearing);
}
return (widths);
}
//
// 'read_maxp()' - Read the number of glyphs in the font.
//
static int // O - Number of glyphs or -1 on error
read_maxp(ttf_t *font) // I - Font
{
// All we care about is the number of glyphs, so just grab that...
if (seek_table(font, TTF_OFF_maxp, 4, true) == 0)
return (-1);
else
return (read_ushort(font));
}
//
// 'read_names()' - Read the name strings from a font.
//
static bool // O - `true` on success, `false` on error
read_names(ttf_t *font) // I - Font
{
unsigned length; // Length of names table
int i, // Looping var
format, // Name table format
offset; // Offset to storage
_ttf_off_name_t *name; // Current name
// Find the name table...
if ((length = seek_table(font, TTF_OFF_name, 0, true)) == 0)
return (false);
if ((format = read_ushort(font)) < 0 || format > 1)
{
errorf(font, "Unsupported name table format %d.", format);
return (false);
}
TTF_DEBUG("read_names: format=%d\n", format);
if ((font->names.num_names = read_ushort(font)) < 1)
return (false);
if ((font->names.names = (_ttf_off_name_t *)calloc((size_t)font->names.num_names, sizeof(_ttf_off_name_t))) == NULL)
return (false);
if ((offset = read_ushort(font)) < 0 || (unsigned)offset >= length)
return (false);
font->names.storage_size = length - (unsigned)offset;
if ((font->names.storage = malloc(font->names.storage_size)) == NULL)
return (false);
memset(font->names.storage, 'A', font->names.storage_size);
for (i = font->names.num_names, name = font->names.names; i > 0; i --, name ++)
{
name->platform_id = (unsigned short)read_ushort(font);
name->encoding_id = (unsigned short)read_ushort(font);
name->language_id = (unsigned short)read_ushort(font);
name->name_id = (unsigned short)read_ushort(font);
name->length = (unsigned short)read_ushort(font);
name->offset = (unsigned short)read_ushort(font);
TTF_DEBUG("name->platform_id=%d, encoding_id=%d, language_id=%d(0x%04x), name_id=%d, length=%d, offset=%d\n", name->platform_id, name->encoding_id, name->language_id, name->language_id, name->name_id, name->length, name->offset);
}
if (format == 1)
{
// Skip language_id table...
int count = read_ushort(font); // Number of language IDs
TTF_DEBUG("read_names: Skipping language_id table...\n");
while (count > 0)
{
/* length = */read_ushort(font);
/* offset = */read_ushort(font);
count --;
}
}
length -= (unsigned)offset;
if (read(font->fd, font->names.storage, length) < 0)
{
errorf(font, "Unable to read name table: %s", strerror(errno));
return (false);
}
return (true);
}
//
// 'read_os_2()' - Read the OS/2 table.
//
static bool // O - `true` on success, `false` on error
read_os_2(ttf_t *font, // I - Font
_ttf_off_os_2_t *os_2) // O - OS/2 table
{
int version; // OS/2 table version
unsigned char panose[10]; // panose value
memset(os_2, 0, sizeof(_ttf_off_os_2_t));
// Find the OS/2 table...
if (seek_table(font, TTF_OFF_OS_2, 0, false) == 0)
return (false);
if ((version = read_ushort(font)) < 0)
return (false);
TTF_DEBUG("read_names: version=%d\n", version);
/* xAvgCharWidth */ read_short(font);
os_2->usWeightClass = (unsigned short)read_ushort(font);
os_2->usWidthClass = (unsigned short)read_ushort(font);
os_2->fsType = (unsigned short)read_ushort(font);
/* ySubscriptXSize */ read_short(font);
/* ySubscriptYSize */ read_short(font);
/* ySubscriptXOffset */ read_short(font);
/* ySubscriptYOffset */ read_short(font);
/* ySuperscriptXSize */ read_short(font);
/* ySuperscriptYSize */ read_short(font);
/* ySuperscriptXOffset */ read_short(font);
/* ySuperscriptYOffset */ read_short(font);
/* yStrikeoutSize */ read_short(font);
/* yStrikeoutOffset */ read_short(font);
/* sFamilyClass */ read_short(font);
/* panose[10] */
if (read(font->fd, panose, sizeof(panose)) != (ssize_t)sizeof(panose))
return (false);
/* ulUnicodeRange1 */ read_ulong(font);
/* ulUnicodeRange2 */ read_ulong(font);
/* ulUnicodeRange3 */ read_ulong(font);
/* ulUnicodeRange4 */ read_ulong(font);
/* achVendID */ read_ulong(font); read_ulong(font);
read_ulong(font); read_ulong(font);
/* fsSelection */ read_ushort(font);
/* usFirstCharIndex */ read_ushort(font);
/* usLastCharIndex */ read_ushort(font);
os_2->sTypoAscender = (short)read_short(font);
os_2->sTypoDescender = (short)read_short(font);
/* sTypoLineGap */ read_short(font);
/* usWinAscent */ read_ushort(font);
/* usWinDescent */ read_ushort(font);
if (version >= 4)
{
/* ulCodePageRange1 */ read_ulong(font);
/* ulCodePageRange2 */ read_ulong(font);
os_2->sxHeight = (short)read_short(font);
os_2->sCapHeight = (short)read_short(font);
}
return (true);
}
//
// 'read_post()' - Read the PostScript table.
//
static bool // O - `true` on success, `false` otherwise
read_post(ttf_t *font, // I - Font
_ttf_off_post_t *post) // I - PostScript table
{
memset(post, 0, sizeof(_ttf_off_post_t));
if (seek_table(font, TTF_OFF_post, 0, false) == 0)
return (false);
/* version = */read_ulong(font);
post->italicAngle = (int)read_ulong(font) / 65536.0f;
/* underlinePosition = */read_ushort(font);
/* underlineThickness = */read_ushort(font);
post->isFixedPitch = read_ulong(font);
return (true);
}
//
// 'read_short()' - Read a 16-bit signed integer.
//
static int // O - 16-bit signed integer value or EOF
read_short(ttf_t *font) // I - Font
{
unsigned char buffer[2]; // Read buffer
if (read(font->fd, buffer, sizeof(buffer)) != sizeof(buffer))
return (EOF);
else if (buffer[0] & 0x80)
return (((buffer[0] << 8) | buffer[1]) - 65536);
else
return ((buffer[0] << 8) | buffer[1]);
}
//
// 'read_table()' - Read an OFF/TTF offset table.
//
static bool // O - `true` on success, `false` on error
read_table(ttf_t *font) // I - Font
{
int i; // Looping var
unsigned temp; // Temporary value
_ttf_off_dir_t *current; // Current table entry
// Read the table header:
//
// Fixed sfnt version (should be 0x10000 for version 1.0)
// USHORT numTables
// USHORT searchRange
// USHORT entrySelector
// USHORT rangeShift
/* sfnt version */
if ((temp = read_ulong(font)) != 0x10000 && temp != 0x4f54544f && temp != 0x74746366)
{
errorf(font, "Invalid font file.");
return (false);
}
if (temp == 0x74746366)
{
// Font collection, get the number of fonts and then seek to the start of
// the offset table for the desired font...
size_t idx; // Current index
TTF_DEBUG("read_table: Font collection\n");
/* Version */
if ((temp = read_ulong(font)) != 0x10000 && temp != 0x20000)
{
errorf(font, "Unsupported font collection version %f.", temp / 65536.0);
return (false);
}
TTF_DEBUG("read_table: Collection version=%f\n", temp / 65536.0);
/* numFonts */
if ((temp = read_ulong(font)) == 0)
{
errorf(font, "No fonts in collection.");
return (false);
}
font->num_fonts = (size_t)temp;
TTF_DEBUG("read_table: numFonts=%u\n", temp);
if (font->idx >= font->num_fonts)
return (false);
/* OffsetTable */
temp = read_ulong(font);
for (idx = font->idx; idx > 0; idx --)
temp = read_ulong(font);
TTF_DEBUG("read_table: Offset for font %u is %u.\n", (unsigned)font->idx, temp);
if (lseek(font->fd, temp + 4, SEEK_SET) < 0)
{
errorf(font, "Unable to seek to font %u: %s", (unsigned)font->idx, strerror(errno));
return (false);
}
}
else
{
// Not a collection so just one font...
font->num_fonts = 1;
}
// numTables
if ((font->table.num_entries = read_ushort(font)) <= 0)
{
errorf(font, "Unable to read font tables.");
return (false);
}
TTF_DEBUG("read_table: num_entries=%u\n", (unsigned)font->table.num_entries);
// searchRange
if (read_ushort(font) < 0)
{
errorf(font, "Unable to read font tables.");
return (false);
}
// entrySelector
if (read_ushort(font) < 0)
{
errorf(font, "Unable to read font tables.");
return (false);
}
// rangeShift
if (read_ushort(font) < 0)
{
errorf(font, "Unable to read font tables.");
return (false);
}
/*
* Read the table entries...
*/
if ((font->table.entries = calloc((size_t)font->table.num_entries, sizeof(_ttf_off_dir_t))) == NULL)
{
errorf(font, "Unable to allocate memory for font tables.");
return (false);
}
for (i = font->table.num_entries, current = font->table.entries; i > 0; i --, current ++)
{
current->tag = read_ulong(font);
current->checksum = read_ulong(font);
current->offset = read_ulong(font);
current->length = read_ulong(font);
TTF_DEBUG("read_table: [%d] tag='%c%c%c%c' checksum=%u offset=%u length=%u\n", i, (current->tag >> 24) & 255, (current->tag >> 16) & 255, (current->tag >> 8) & 255, current->tag & 255, current->checksum, current->offset, current->length);
}
return (true);
}
//
// 'read_ulong()' - Read a 32-bit unsigned integer.
//
static unsigned // O - 32-bit unsigned integer value or EOF
read_ulong(ttf_t *font) // I - Font
{
unsigned char buffer[4]; // Read buffer
if (read(font->fd, buffer, sizeof(buffer)) != sizeof(buffer))
return ((unsigned)EOF);
else
return ((unsigned)((buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]));
}
//
// 'read_ushort()' - Read a 16-bit unsigned integer.
//
static int // O - 16-bit unsigned integer value or EOF
read_ushort(ttf_t *font) // I - Font
{
unsigned char buffer[2]; // Read buffer
if (read(font->fd, buffer, sizeof(buffer)) != sizeof(buffer))
return (EOF);
else
return ((buffer[0] << 8) | buffer[1]);
}
//
// 'seek_table()' - Seek to a specific table in a font.
//
static unsigned // O - Length of table or 0 if not found
seek_table(ttf_t *font, // I - Font
unsigned tag, // I - Tag to find
unsigned offset, // I - Additional offset
bool required) // I - Required table?
{
int i; // Looping var
_ttf_off_dir_t *current; // Current entry
// Look up the tag in the table...
for (i = font->table.num_entries, current = font->table.entries; i > 0; i --, current ++)
{
if (current->tag == tag)
{
// Found it, seek and return...
if (lseek(font->fd, current->offset + offset, SEEK_SET) == (current->offset + offset))
{
// Successful seek...
return (current->length - offset);
}
else
{
// Seek failed...
errorf(font, "Unable to seek to %c%c%c%c table: %s", (tag >> 24) & 255, (tag >> 16) & 255, (tag >> 8) & 255, tag & 255, strerror(errno));
return (0);
}
}
}
// Not found, return 0...
if (required)
errorf(font, "%c%c%c%c table not found.", (tag >> 24) & 255, (tag >> 16) & 255, (tag >> 8) & 255, tag & 255);
return (0);
}
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