| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: txport.h,v 1.2 2002/01/30 09:27:10 mdw Exp $ |
| 4 | * |
| 5 | * Transport switch glue |
| 6 | * |
| 7 | * (c) 2001 Mark Wooding |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Jog: Programming for a jogging machine. |
| 13 | * |
| 14 | * Jog is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * Jog is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with Jog; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | #ifndef TXPORTSW_H |
| 30 | #define TXPORTSW_H |
| 31 | |
| 32 | #ifdef __cplusplus |
| 33 | extern "C" { |
| 34 | #endif |
| 35 | |
| 36 | /*----- Header files ------------------------------------------------------*/ |
| 37 | |
| 38 | #ifdef HAVE_CONFIG_H |
| 39 | # include "config.h" |
| 40 | #endif |
| 41 | |
| 42 | #include <stdarg.h> |
| 43 | #include <stddef.h> |
| 44 | |
| 45 | #include <pthread.h> |
| 46 | |
| 47 | #include <mLib/darray.h> |
| 48 | #include <mLib/lbuf.h> |
| 49 | |
| 50 | /*----- Data structures ---------------------------------------------------*/ |
| 51 | |
| 52 | /* --- Vector of bytes --- */ |
| 53 | |
| 54 | #ifndef UCHAR_V |
| 55 | # define UCHAR_V |
| 56 | DA_DECL(uchar_v, unsigned char); |
| 57 | #endif |
| 58 | |
| 59 | /* --- Node for lines --- */ |
| 60 | |
| 61 | typedef struct txline { |
| 62 | struct txline *next, *prev; /* Next node in the list */ |
| 63 | struct txport *tx; /* Owning transport */ |
| 64 | char *s; /* Pointer to the text */ |
| 65 | size_t len; /* Length of the string */ |
| 66 | } txline; |
| 67 | |
| 68 | /* --- A transport context --- * |
| 69 | * |
| 70 | * The only members for which there is contention are the state @s@ and the |
| 71 | * raw incoming buffer @buf@. Other members may be accessed without locking |
| 72 | * the structure. Thus, the thread messing about is essentially isolated to |
| 73 | * the data- fetching thread and the line buffering code. |
| 74 | */ |
| 75 | |
| 76 | typedef struct txport { |
| 77 | struct txport_ops *ops; /* Operations table */ |
| 78 | pthread_t tid; /* Fetching thread id */ |
| 79 | pthread_mutex_t mx; /* Lock for this structure */ |
| 80 | pthread_cond_t cv; /* `New data has arrived' */ |
| 81 | unsigned s; /* State of this transport */ |
| 82 | uchar_v buf; /* Buffer of incoming data */ |
| 83 | lbuf lb; /* Buffer for extracting lines */ |
| 84 | txline *ll, *ll_tail; /* List of waiting lines, in order */ |
| 85 | } txport; |
| 86 | |
| 87 | enum { |
| 88 | TX_READY, /* More data may arrive */ |
| 89 | TX_CLOSE, /* No more data will arrive */ |
| 90 | TX_CLOSED /* Done the closure thing already */ |
| 91 | }; |
| 92 | |
| 93 | /* --- Transport operations --- */ |
| 94 | |
| 95 | struct txfile { const char *env; const char *name; }; |
| 96 | |
| 97 | typedef struct txport_ops { |
| 98 | struct txport_ops *next; |
| 99 | const char *name; |
| 100 | const struct txfile *fv; |
| 101 | const char *config; |
| 102 | txport *(*create)(const char */*file*/); |
| 103 | int (*configure)(txport */*tx*/, const char */*k*/, const char */*v*/); |
| 104 | void *(*fetch)(void */*txv*/); |
| 105 | ssize_t (*write)(txport */*tx*/, const void */*p*/, size_t /*sz*/); |
| 106 | void (*destroy)(txport */*tx*/); |
| 107 | } txport_ops; |
| 108 | |
| 109 | /*----- Global variables --------------------------------------------------*/ |
| 110 | |
| 111 | extern txport_ops *txlist; |
| 112 | extern const char *txname; |
| 113 | extern const char *txfile; |
| 114 | extern const char *txconf; |
| 115 | |
| 116 | #define DIRVAR "JOGDIR" |
| 117 | |
| 118 | /*----- Functions provided ------------------------------------------------*/ |
| 119 | |
| 120 | /* --- @tx_create@ --- * |
| 121 | * |
| 122 | * Arguments: @const char *name@ = name of transport to instantiate |
| 123 | * @const char *file@ = filename for transport |
| 124 | * @const char *config@ = config string |
| 125 | * |
| 126 | * Returns: A pointer to the transport context, or null on error. |
| 127 | * |
| 128 | * Use: Creates a new transport. |
| 129 | */ |
| 130 | |
| 131 | extern txport *tx_create(const char */*name*/, const char */*file*/, |
| 132 | const char */*config*/); |
| 133 | |
| 134 | /* --- @tx_configure@ --- * |
| 135 | * |
| 136 | * Arguments: @txport *tx@ = pointer to transport block |
| 137 | * @const char *config@ = config string |
| 138 | * |
| 139 | * Returns: Zero if OK, nonzero on errors. |
| 140 | * |
| 141 | * Use: Applies a configuration string to a transport. |
| 142 | */ |
| 143 | |
| 144 | extern int tx_configure(txport */*tx*/, const char */*config*/); |
| 145 | |
| 146 | /* --- @tx_write@ --- * |
| 147 | * |
| 148 | * Arguments: @txport *tx@ = pointer to transport context |
| 149 | * @const void *p@ = pointer to buffer to write |
| 150 | * @size_t sz@ = size of buffer |
| 151 | * |
| 152 | * Returns: Zero if OK, or @-1@ on error. |
| 153 | * |
| 154 | * Use: Writes some data to a transport. |
| 155 | */ |
| 156 | |
| 157 | extern int tx_write(txport */*tx*/, const void */*p*/, size_t /*sz*/); |
| 158 | |
| 159 | /* --- @tx_printf@ --- * |
| 160 | * |
| 161 | * Arguments: @txport *tx@ = pointer to transport context |
| 162 | * @const char *p@ = pointer to string to write |
| 163 | * |
| 164 | * Returns: The number of characters printed, or @EOF@ on error. |
| 165 | * |
| 166 | * Use: Writes a textual message to a transport. |
| 167 | */ |
| 168 | |
| 169 | extern int tx_vprintf(txport */*tx*/, const char */*p*/, va_list */*ap*/); |
| 170 | |
| 171 | extern int tx_printf(txport */*tx*/, const char */*p*/, ...); |
| 172 | |
| 173 | /* --- @tx_newline@ --- * |
| 174 | * |
| 175 | * Arguments: @txport *tx@ = pointer to transport context |
| 176 | * |
| 177 | * Returns: Zero if OK, nonzero on error. |
| 178 | * |
| 179 | * Use: Writes a newline (record boundary) to the output. |
| 180 | */ |
| 181 | |
| 182 | int tx_newline(txport */*tx*/); |
| 183 | |
| 184 | /* --- @tx_read@, @tx_readx@ --- * |
| 185 | * |
| 186 | * Arguments: @txport *tx@ = pointer to transport context |
| 187 | * @unsigned long t@ = time to wait for data (ms) |
| 188 | * @int (*filter)(const char *s, void *p)@ = filtering function |
| 189 | * @void *p@ = pointer argument for filter |
| 190 | * |
| 191 | * Returns: A pointer to a line block, which must be freed using |
| 192 | * @tx_freeline@. |
| 193 | * |
| 194 | * Use: Fetches a line from the buffer. Each line is passed to the |
| 195 | * filter function in oldest-to-newest order; the filter |
| 196 | * function returns nonzero to choose a line. If no suitable |
| 197 | * line is waiting in the raw buffer, the program blocks while |
| 198 | * more data is fetched, until the time limit @t@ is exceeded, |
| 199 | * in which case a null pointer is returned. A null filter |
| 200 | * function is equivalent to one which always selects its line. |
| 201 | */ |
| 202 | |
| 203 | #define FOREVER (~0ul) |
| 204 | |
| 205 | extern txline *tx_readx(txport */*tx*/, unsigned long /*t*/, |
| 206 | int (*/*filter*/)(const char */*s*/, void */*p*/), |
| 207 | void */*p*/); |
| 208 | |
| 209 | extern txline *tx_read(txport */*tx*/, unsigned long /*t*/); |
| 210 | |
| 211 | /* --- @tx_freeline@ --- * |
| 212 | * |
| 213 | * Arguments: @txline *l@ = pointer to line |
| 214 | * |
| 215 | * Returns: --- |
| 216 | * |
| 217 | * Use: Frees a line block. |
| 218 | */ |
| 219 | |
| 220 | extern void tx_freeline(txline */*l*/); |
| 221 | |
| 222 | /* --- @tx_destroy@ --- * |
| 223 | * |
| 224 | * Arguments: @txport *tx@ = transport context |
| 225 | * |
| 226 | * Returns: --- |
| 227 | * |
| 228 | * Use: Destroys a transport. |
| 229 | */ |
| 230 | |
| 231 | extern void tx_destroy(txport */*tx*/); |
| 232 | |
| 233 | /*----- That's all, folks -------------------------------------------------*/ |
| 234 | |
| 235 | #ifdef __cplusplus |
| 236 | } |
| 237 | #endif |
| 238 | |
| 239 | #endif |