| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Abstract interface to codecs |
| 4 | * |
| 5 | * (c) 2009 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of the mLib utilities library. |
| 11 | * |
| 12 | * mLib is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU Library General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * mLib is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU Library General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with mLib; if not, write to the Free |
| 24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 25 | * MA 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | #ifndef MLIB_CODEC_H |
| 29 | #define MLIB_CODEC_H |
| 30 | |
| 31 | #ifdef __cplusplus |
| 32 | extern "C" { |
| 33 | #endif |
| 34 | |
| 35 | /*----- Header files ------------------------------------------------------*/ |
| 36 | |
| 37 | #ifndef MLIB_DSTR_H |
| 38 | # include "dstr.h" |
| 39 | #endif |
| 40 | |
| 41 | /*----- Data structures ---------------------------------------------------*/ |
| 42 | |
| 43 | typedef struct codec { |
| 44 | const struct codec_ops *ops; |
| 45 | } codec; |
| 46 | |
| 47 | typedef struct codec_class { |
| 48 | const char *name; |
| 49 | codec *(*encoder)(unsigned /*flags*/, |
| 50 | const char */*indent*/, unsigned /*maxline*/); |
| 51 | codec *(*decoder)(unsigned /*flags*/); |
| 52 | |
| 53 | #define CDCF_LOWERC 1u /* Prefer lower case */ |
| 54 | #define CDCF_IGNCASE 2u /* Ignore case on input */ |
| 55 | #define CDCF_NOEQPAD 4u /* No `=' padding */ |
| 56 | #define CDCF_IGNEQPAD 8u /* Ignore `=' pad errors on input */ |
| 57 | #define CDCF_IGNEQMID 16u /* Ignore pad chars on input */ |
| 58 | #define CDCF_IGNZPAD 32u /* Ignore zero padding on input */ |
| 59 | #define CDCF_IGNNEWL 64u /* Ignore newlines on input */ |
| 60 | #define CDCF_IGNINVCH 128u /* Ignore invalid chars on input */ |
| 61 | |
| 62 | #define CDCF_IGNJUNK /* Ignore all bad things */ \ |
| 63 | (CDCF_IGNEQMID | CDCF_IGNZPAD | \ |
| 64 | CDCF_IGNCASE | CDCF_IGNNEWL | CDCF_IGNINVCH) |
| 65 | |
| 66 | } codec_class; |
| 67 | |
| 68 | #define CODEC_ERRORS(_) \ |
| 69 | _(OK, "No error") \ |
| 70 | _(INVCH, "Invalid character") \ |
| 71 | _(INVEQPAD, "Invalid padding character") \ |
| 72 | _(INVZPAD, "Nonzero padding bits") |
| 73 | enum { |
| 74 | #define DECLERR(name, text) CDCERR_##name, |
| 75 | CODEC_ERRORS(DECLERR) |
| 76 | #undef DECLERR |
| 77 | CDCERR__LIMIT |
| 78 | }; |
| 79 | |
| 80 | typedef struct codec_ops { |
| 81 | const codec_class *c; |
| 82 | int (*code)(codec */*c*/, const void */*p*/, size_t /*sz*/, dstr */*d*/); |
| 83 | void (*destroy)(codec */*c*/); |
| 84 | } codec_ops; |
| 85 | |
| 86 | /*----- Functions provided ------------------------------------------------*/ |
| 87 | |
| 88 | /* --- @codec_strerror@ --- * |
| 89 | * |
| 90 | * Arguments: @int err@ = error code from codec |
| 91 | * |
| 92 | * Returns: Pointer to error text. |
| 93 | * |
| 94 | * Use: Converts error codes to human-readable strings. |
| 95 | */ |
| 96 | |
| 97 | const char *codec_strerror(int /*err*/); |
| 98 | |
| 99 | /*----- Null codec --------------------------------------------------------*/ |
| 100 | |
| 101 | extern const codec_class null_codec_class; |
| 102 | |
| 103 | /*----- That's all, folks -------------------------------------------------*/ |
| 104 | |
| 105 | #ifdef __cplusplus |
| 106 | } |
| 107 | #endif |
| 108 | |
| 109 | #endif |