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Diffstat (limited to 'src/3rdparty/freetype/docs/DEBUG')
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diff --git a/src/3rdparty/freetype/docs/DEBUG b/src/3rdparty/freetype/docs/DEBUG deleted file mode 100644 index 1fccc21c4..000000000 --- a/src/3rdparty/freetype/docs/DEBUG +++ /dev/null @@ -1,199 +0,0 @@ -Debugging within the FreeType sources -===================================== - -I. Configuration macros ------------------------ - -There are several ways to enable debugging features in a FreeType 2 -builds. This is controlled through the definition of special macros -located in the file `ftoptions.h'. The macros are: - - - FT_DEBUG_LEVEL_ERROR - - #define this macro if you want to compile the FT_ERROR macro calls - to print error messages during program execution. This will not - stop the program. Very useful to spot invalid fonts during - development and to code workarounds for them. - - FT_DEBUG_LEVEL_TRACE - - #define this macro if you want to compile both macros FT_ERROR and - FT_TRACE. This also includes the variants FT_TRACE0, FT_TRACE1, - FT_TRACE2, ..., FT_TRACE7. - - The trace macros are used to send debugging messages when an - appropriate `debug level' is configured at runtime through the - FT2_DEBUG environment variable (more on this later). - - FT_DEBUG_MEMORY - - If this macro is #defined, the FreeType engine is linked with a - small but effective debugging memory manager that tracks all - allocations and frees that are performed within the font engine. - - When the FT2_DEBUG_MEMORY environment variable is defined at - runtime, a call to FT_Done_FreeType will dump memory statistics, - including the list of leaked memory blocks with the source locations - where these were allocated. It is always a very good idea to define - this in development builds. This works with _any_ program linked to - FreeType, but requires a big deal of memory (the debugging memory - manager never frees the blocks to the heap in order to detect double - frees). - - When FT2_DEBUG_MEMORY isn't defined at runtime, the debugging memory - manager is ignored, and performance is unaffected. - - -II. Debugging macros --------------------- - -Several macros can be used within the FreeType sources to help debugging -its code: - - - 1. FT_ERROR(( ... )) - - This macro is used to send debug messages that indicate relatively - serious errors (like broken font files), but will not stop the - execution of the running program. Its code is compiled only when - either FT_DEBUG_LEVEL_ERROR or FT_DEBUG_LEVEL_TRACE are defined in - `ftoption.h'. - - Note that you have to use a printf-like signature, but with double - parentheses, like in - - FT_ERROR(( "your %s is not %s\n", "foo", "bar" )); - - - 2. FT_ASSERT( condition ) - - This macro is used to check strong assertions at runtime. If its - condition isn't TRUE, the program will abort with a panic message. - Its code is compiled when either FT_DEBUG_LEVEL_ERROR or - FT_DEBUG_LEVEL_TRACE are defined. You don't need double parentheses - here. For example - - FT_ASSERT( ptr != NULL ); - - - 3. FT_TRACE( level, (message...) ) - - The FT_TRACE macro is used to send general-purpose debugging - messages during program execution. This macro uses an *implicit* - macro named FT_COMPONENT used to name the current FreeType component - being run. - - The developer should always define FT_COMPONENT as appropriate, for - example as in - - #undef FT_COMPONENT - #define FT_COMPONENT trace_io - - The value of the FT_COMPONENT macro is an enumeration named - trace_XXXX where XXXX is one of the component names defined in the - internal file `freetype/internal/fttrace.h'. - - Each such component is assigned a `debug level', ranging from 0 - to 7, through the use of the FT2_DEBUG environment variable - (described below) when a program linked with FreeType starts. - - When FT_TRACE is called, its level is compared to the one of the - corresponding component. Messages with trace levels *higher* than - the corresponding component level are filtered and never printed. - - This means that trace messages with level 0 are always printed, - those with level 2 are only printed when the component level is *at - least* 2. - - The second parameter to FT_TRACE must contain parentheses and - correspond to a printf-like call, as in - - FT_TRACE( 2, ( "your %s is not %s\n", "foo", "bar" ) ) - - The shortcut macros FT_TRACE0, FT_TRACE1, FT_TRACE2, ..., FT_TRACE7 - can be used with constant level indices, and are much cleaner to - use, as in - - FT_TRACE2(( "your %s is not %s\n", "foo", "bar" )); - - -III. Environment variables --------------------------- - -The following environment variables control debugging output and -behaviour of FreeType at runtime. - - - FT2_DEBUG - - This variable is only used when FreeType is built with - FT_DEBUG_LEVEL_TRACE defined. It contains a list of component level - definitions, following this format: - - component1:level1 component2:level2 component3:level3 ... - - where `componentX' is the name of a tracing component, as defined in - `fttrace.h', but without the `trace_' prefix. `levelX' is the - corresponding level to use at runtime. - - `any' is a special component name that will be interpreted as - `any/all components'. For example, the following definitions - - set FT2_DEBUG=any:2 memory:5 io:4 (on Windows) - export FT2_DEBUG="any:2 memory:5 io:4" (on Linux with bash) - - both stipulate that all components should have level 2, except for - the memory and io components which will be set to trace levels 5 and - 4, respectively. - - - FT2_DEBUG_MEMORY - - This environment variable, when defined, tells FreeType to use a - debugging memory manager that will track leaking memory blocks as - well as other common errors like double frees. It is also capable - of reporting _where_ the leaking blocks were allocated, which - considerably saves time when debugging new additions to the library. - - This code is only compiled when FreeType is built with the - FT_DEBUG_MEMORY macro #defined in `ftoption.h' though, it will be - ignored in other builds. - - - FT2_ALLOC_TOTAL_MAX - - This variable is ignored if FT2_DEBUG_MEMORY is not defined. It - allows you to specify a maximum heap size for all memory allocations - performed by FreeType. This is very useful to test the robustness - of the font engine and programs that use it in tight memory - conditions. - - If it is undefined, or if its value is not strictly positive, then - no allocation bounds are checked at runtime. - - - FT2_ALLOC_COUNT_MAX - - This variable is ignored if FT2_DEBUG_MEMORY is not defined. It - allows you to specify a maximum number of memory allocations - performed by FreeType before returning the error - FT_Err_Out_Of_Memory. This is useful for debugging and testing the - engine's robustness. - - If it is undefined, or if its value is not strictly positive, then - no allocation bounds are checked at runtime. - ------------------------------------------------------------------------- - -Copyright 2002, 2003, 2004, 2005 by -David Turner, Robert Wilhelm, and Werner Lemberg. - -This file is part of the FreeType project, and may only be used, -modified, and distributed under the terms of the FreeType project -license, LICENSE.TXT. By continuing to use, modify, or distribute this -file you indicate that you have read the license and understand and -accept it fully. - - ---- end of DEBUG --- |