1 /***************************************************************************/ 2 /* */ 3 /* cf2error.h */ 4 /* */ 5 /* Adobe's code for error handling (specification). */ 6 /* */ 7 /* Copyright 2006-2013 Adobe Systems Incorporated. */ 8 /* */ 9 /* This software, and all works of authorship, whether in source or */ 10 /* object code form as indicated by the copyright notice(s) included */ 11 /* herein (collectively, the "Work") is made available, and may only be */ 12 /* used, modified, and distributed under the FreeType Project License, */ 13 /* LICENSE.TXT. Additionally, subject to the terms and conditions of the */ 14 /* FreeType Project License, each contributor to the Work hereby grants */ 15 /* to any individual or legal entity exercising permissions granted by */ 16 /* the FreeType Project License and this section (hereafter, "You" or */ 17 /* "Your") a perpetual, worldwide, non-exclusive, no-charge, */ 18 /* royalty-free, irrevocable (except as stated in this section) patent */ 19 /* license to make, have made, use, offer to sell, sell, import, and */ 20 /* otherwise transfer the Work, where such license applies only to those */ 21 /* patent claims licensable by such contributor that are necessarily */ 22 /* infringed by their contribution(s) alone or by combination of their */ 23 /* contribution(s) with the Work to which such contribution(s) was */ 24 /* submitted. If You institute patent litigation against any entity */ 25 /* (including a cross-claim or counterclaim in a lawsuit) alleging that */ 26 /* the Work or a contribution incorporated within the Work constitutes */ 27 /* direct or contributory patent infringement, then any patent licenses */ 28 /* granted to You under this License for that Work shall terminate as of */ 29 /* the date such litigation is filed. */ 30 /* */ 31 /* By using, modifying, or distributing the Work you indicate that you */ 32 /* have read and understood the terms and conditions of the */ 33 /* FreeType Project License as well as those provided in this section, */ 34 /* and you accept them fully. */ 35 /* */ 36 /***************************************************************************/ 37 38 39 #ifndef __CF2ERROR_H__ 40 #define __CF2ERROR_H__ 41 42 43 #include FT_MODULE_ERRORS_H 44 45 #undef __FTERRORS_H__ 46 47 #undef FT_ERR_PREFIX 48 #define FT_ERR_PREFIX CF2_Err_ 49 #define FT_ERR_BASE FT_Mod_Err_CF2 50 51 52 #include FT_ERRORS_H 53 #include "cf2ft.h" 54 55 56 FT_BEGIN_HEADER 57 58 59 /* 60 * A poor-man error facility. 61 * 62 * This code being written in vanilla C, doesn't have the luxury of a 63 * language-supported exception mechanism such as the one available in 64 * Java. Instead, we are stuck with using error codes that must be 65 * carefully managed and preserved. However, it is convenient for us to 66 * model our error mechanism on a Java-like exception mechanism. 67 * When we assign an error code we are thus `throwing' an error. 68 * 69 * The perservation of an error code is done by coding convention. 70 * Upon a function call if the error code is anything other than 71 * `FT_Err_Ok', which is guaranteed to be zero, we 72 * will return without altering that error. This will allow the 73 * error to propogate and be handled at the appropriate location in 74 * the code. 75 * 76 * This allows a style of code where the error code is initialized 77 * up front and a block of calls are made with the error code only 78 * being checked after the block. If a new error occurs, the original 79 * error will be preserved and a functional no-op should result in any 80 * subsequent function that has an initial error code not equal to 81 * `FT_Err_Ok'. 82 * 83 * Errors are encoded by calling the `FT_THROW' macro. For example, 84 * 85 * { 86 * FT_Error e; 87 * 88 * 89 * ... 90 * e = FT_THROW( Out_Of_Memory ); 91 * } 92 * 93 */ 94 95 96 /* Set error code to a particular value. */ 97 FT_LOCAL( void ) 98 cf2_setError( FT_Error* error, 99 FT_Error value ); 100 101 102 /* 103 * A macro that conditionally sets an error code. 104 * 105 * This macro will first check whether `error' is set; 106 * if not, it will set it to `e'. 107 * 108 */ 109 #define CF2_SET_ERROR( error, e ) \ 110 cf2_setError( error, FT_THROW( e ) ) 111 112 113 FT_END_HEADER 114 115 116 #endif /* __CF2ERROR_H__ */ 117 118 119 /* END */ 120
