| 1 | /**************************************************************************** |
| 2 | * |
| 3 | * pserror.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 PSERROR_H_ |
| 40 | #define PSERROR_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 "psft.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 preservation 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 propagate 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 /* PSERROR_H_ */ |
| 117 | |
| 118 | |
| 119 | /* END */ |
| 120 | |