1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 1997-2001 by Sun Microsystems, Inc. 24 * All rights reserved. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 /* 30 * String I/O Backend 31 * 32 * Simple backend to provide the ability to perform i/o reads from an in-memory 33 * string. This allows us to mdb_eval() a string -- by creating an i/o object 34 * out of it, we can then pass it to the parser as stdin. 35 */ 36 37 #include <mdb/mdb_modapi.h> 38 #include <mdb/mdb_io_impl.h> 39 #include <mdb/mdb_string.h> 40 #include <mdb/mdb_err.h> 41 42 typedef struct str_data { 43 char *str_base; /* Pointer to private copy of string */ 44 char *str_ptr; /* Current seek pointer */ 45 size_t str_len; /* Length of string */ 46 } str_data_t; 47 48 static ssize_t 49 strio_read(mdb_io_t *io, void *buf, size_t nbytes) 50 { 51 str_data_t *sd = io->io_data; 52 size_t left = sd->str_base + sd->str_len - sd->str_ptr; 53 54 if (left != 0) { 55 size_t obytes = nbytes < left ? nbytes : left; 56 (void) strncpy(buf, sd->str_ptr, obytes); 57 sd->str_ptr += obytes; 58 return (obytes); 59 } 60 61 return (0); /* At end of string: return EOF */ 62 } 63 64 static off64_t 65 strio_seek(mdb_io_t *io, off64_t offset, int whence) 66 { 67 str_data_t *sd = io->io_data; 68 char *nptr; 69 70 if (io->io_next != NULL) 71 return (IOP_SEEK(io->io_next, offset, whence)); 72 73 switch (whence) { 74 case SEEK_SET: 75 nptr = sd->str_base + offset; 76 break; 77 case SEEK_CUR: 78 nptr = sd->str_ptr + offset; 79 break; 80 case SEEK_END: 81 nptr = sd->str_base + sd->str_len + offset; 82 break; 83 default: 84 return (set_errno(EINVAL)); 85 } 86 87 if (nptr < sd->str_base || nptr > sd->str_ptr + sd->str_len) 88 return (set_errno(EINVAL)); 89 90 sd->str_ptr = nptr; 91 return ((off64_t)(nptr - sd->str_base)); 92 } 93 94 static void 95 strio_close(mdb_io_t *io) 96 { 97 str_data_t *sd = io->io_data; 98 99 strfree(sd->str_base); 100 mdb_free(sd, sizeof (str_data_t)); 101 } 102 103 static const char * 104 strio_name(mdb_io_t *io) 105 { 106 if (io->io_next != NULL) 107 return (IOP_NAME(io->io_next)); 108 109 return ("(string)"); 110 } 111 112 static const mdb_io_ops_t strio_ops = { 113 strio_read, 114 no_io_write, 115 strio_seek, 116 no_io_ctl, 117 strio_close, 118 strio_name, 119 no_io_link, 120 no_io_unlink, 121 no_io_setattr, 122 no_io_suspend, 123 no_io_resume 124 }; 125 126 mdb_io_t * 127 mdb_strio_create(const char *s) 128 { 129 mdb_io_t *io = mdb_alloc(sizeof (mdb_io_t), UM_SLEEP); 130 str_data_t *sd = mdb_alloc(sizeof (str_data_t), UM_SLEEP); 131 132 /* 133 * Our parser expects each command to end with '\n' or ';'. To 134 * simplify things for the caller, we append a trailing newline 135 * so the argvec string can be passed directly sans modifications. 136 */ 137 sd->str_len = strlen(s) + 1; 138 sd->str_base = strndup(s, sd->str_len); 139 (void) strcat(sd->str_base, "\n"); 140 sd->str_ptr = sd->str_base; 141 142 io->io_ops = &strio_ops; 143 io->io_data = sd; 144 io->io_next = NULL; 145 io->io_refcnt = 0; 146 147 return (io); 148 } 149 150 int 151 mdb_iob_isastr(mdb_iob_t *iob) 152 { 153 mdb_io_t *io; 154 155 for (io = iob->iob_iop; io != NULL; io = io->io_next) { 156 if (io->io_ops == &strio_ops) 157 return (1); 158 } 159 160 return (0); 161 } 162