[2890] | 1 | |
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| 2 | /* |
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| 3 | * RpOp.c -- |
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| 4 | * |
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| 5 | * This module implements utility procedures for the BLT toolkit. |
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| 6 | * |
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| 7 | * Copyright 1991-2004 George A Howlett. |
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| 8 | * |
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| 9 | * Permission is hereby granted, free of charge, to any person |
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| 10 | * obtaining a copy of this software and associated documentation |
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| 11 | * files (the "Software"), to deal in the Software without |
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| 12 | * restriction, including without limitation the rights to use, |
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| 13 | * copy, modify, merge, publish, distribute, sublicense, and/or |
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| 14 | * sell copies of the Software, and to permit persons to whom the |
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| 15 | * Software is furnished to do so, subject to the following |
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| 16 | * conditions: |
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| 17 | * |
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| 18 | * The above copyright notice and this permission notice shall be |
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| 19 | * included in all copies or substantial portions of the |
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| 20 | * Software. |
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| 21 | * |
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| 22 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY |
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| 23 | * KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE |
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| 24 | * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR |
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| 25 | * PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS |
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| 26 | * OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR |
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| 27 | * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR |
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| 28 | * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE |
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| 29 | * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
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| 30 | */ |
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| 31 | |
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| 32 | #include <tcl.h> |
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| 33 | #include <string.h> |
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| 34 | #include "RpOp.h" |
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| 35 | /* |
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| 36 | *--------------------------------------------------------------------------- |
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| 37 | * |
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| 38 | * BinaryOpSearch -- |
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| 39 | * |
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| 40 | * Performs a binary search on the array of command operation |
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| 41 | * specifications to find a partial, anchored match for the given |
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| 42 | * operation string. |
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| 43 | * |
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| 44 | * Results: |
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| 45 | * If the string matches unambiguously the index of the specification in |
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| 46 | * the array is returned. If the string does not match, even as an |
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| 47 | * abbreviation, any operation, -1 is returned. If the string matches, |
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| 48 | * but ambiguously -2 is returned. |
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| 49 | * |
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| 50 | *--------------------------------------------------------------------------- |
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| 51 | */ |
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| 52 | static int |
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| 53 | BinaryOpSearch( |
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| 54 | Rp_OpSpec *specs, |
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| 55 | int nSpecs, |
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| 56 | char *string) /* Name of minor operation to search for */ |
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| 57 | { |
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| 58 | char c; |
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| 59 | int high, low; |
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| 60 | size_t length; |
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| 61 | |
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| 62 | low = 0; |
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| 63 | high = nSpecs - 1; |
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| 64 | c = string[0]; |
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| 65 | length = strlen(string); |
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| 66 | while (low <= high) { |
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| 67 | Rp_OpSpec *specPtr; |
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| 68 | int compare; |
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| 69 | int median; |
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| 70 | |
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| 71 | median = (low + high) >> 1; |
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| 72 | specPtr = specs + median; |
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| 73 | |
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| 74 | /* Test the first character */ |
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| 75 | compare = c - specPtr->name[0]; |
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| 76 | if (compare == 0) { |
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| 77 | /* Now test the entire string */ |
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| 78 | compare = strncmp(string, specPtr->name, length); |
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| 79 | if (compare == 0) { |
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| 80 | if ((int)length < specPtr->minChars) { |
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| 81 | return -2; /* Ambiguous operation name */ |
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| 82 | } |
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| 83 | } |
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| 84 | } |
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| 85 | if (compare < 0) { |
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| 86 | high = median - 1; |
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| 87 | } else if (compare > 0) { |
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| 88 | low = median + 1; |
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| 89 | } else { |
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| 90 | return median; /* Op found. */ |
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| 91 | } |
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| 92 | } |
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| 93 | return -1; /* Can't find operation */ |
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| 94 | } |
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| 95 | |
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| 96 | /* |
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| 97 | *--------------------------------------------------------------------------- |
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| 98 | * |
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| 99 | * LinearOpSearch -- |
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| 100 | * |
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| 101 | * Performs a binary search on the array of command operation |
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| 102 | * specifications to find a partial, anchored match for the given |
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| 103 | * operation string. |
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| 104 | * |
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| 105 | * Results: |
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| 106 | * If the string matches unambiguously the index of the specification in |
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| 107 | * the array is returned. If the string does not match, even as an |
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| 108 | * abbreviation, any operation, -1 is returned. If the string matches, |
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| 109 | * but ambiguously -2 is returned. |
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| 110 | * |
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| 111 | *--------------------------------------------------------------------------- |
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| 112 | */ |
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| 113 | static int |
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| 114 | LinearOpSearch( |
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| 115 | Rp_OpSpec *specs, |
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| 116 | int nSpecs, |
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| 117 | char *string) /* Name of minor operation to search for */ |
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| 118 | { |
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| 119 | Rp_OpSpec *specPtr; |
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| 120 | char c; |
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| 121 | size_t length; |
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| 122 | int nMatches, last; |
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| 123 | int i; |
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| 124 | |
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| 125 | c = string[0]; |
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| 126 | length = strlen(string); |
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| 127 | nMatches = 0; |
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| 128 | last = -1; |
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| 129 | for (specPtr = specs, i = 0; i < nSpecs; i++, specPtr++) { |
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| 130 | if ((c == specPtr->name[0]) && |
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| 131 | (strncmp(string, specPtr->name, length) == 0)) { |
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| 132 | last = i; |
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| 133 | nMatches++; |
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| 134 | if ((int)length == specPtr->minChars) { |
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| 135 | break; |
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| 136 | } |
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| 137 | } |
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| 138 | } |
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| 139 | if (nMatches > 1) { |
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| 140 | return -2; /* Ambiguous operation name */ |
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| 141 | } |
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| 142 | if (nMatches == 0) { |
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| 143 | return -1; /* Can't find operation */ |
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| 144 | } |
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| 145 | return last; /* Op found. */ |
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| 146 | } |
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| 147 | |
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| 148 | /* |
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| 149 | *--------------------------------------------------------------------------- |
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| 150 | * |
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| 151 | * Rp_GetOpFromObj -- |
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| 152 | * |
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| 153 | * Find the command operation given a string name. This is useful where |
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| 154 | * a group of command operations have the same argument signature. |
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| 155 | * |
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| 156 | * Results: |
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| 157 | * If found, a pointer to the procedure (function pointer) is returned. |
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| 158 | * Otherwise NULL is returned and an error message containing a list of |
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| 159 | * the possible commands is returned in interp->result. |
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| 160 | * |
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| 161 | *--------------------------------------------------------------------------- |
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| 162 | */ |
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| 163 | void * |
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| 164 | Rp_GetOpFromObj( |
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| 165 | Tcl_Interp *interp, /* Interpreter to report errors to */ |
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| 166 | int nSpecs, /* Number of specifications in array */ |
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| 167 | Rp_OpSpec *specs, /* Op specification array */ |
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| 168 | int operPos, /* Position of operation in argument list. */ |
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| 169 | int objc, /* Number of arguments in the argument vector. |
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| 170 | * This includes any prefixed arguments */ |
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| 171 | Tcl_Obj *const *objv, /* Argument vector */ |
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| 172 | int flags) |
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| 173 | { |
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| 174 | Rp_OpSpec *specPtr; |
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| 175 | char *string; |
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| 176 | int n; |
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| 177 | |
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| 178 | if (objc <= operPos) { /* No operation argument */ |
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| 179 | Tcl_AppendResult(interp, "wrong # args: ", (char *)NULL); |
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| 180 | usage: |
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| 181 | Tcl_AppendResult(interp, "should be one of...", (char *)NULL); |
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| 182 | for (n = 0; n < nSpecs; n++) { |
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| 183 | int i; |
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| 184 | |
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| 185 | Tcl_AppendResult(interp, "\n ", (char *)NULL); |
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| 186 | for (i = 0; i < operPos; i++) { |
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| 187 | Tcl_AppendResult(interp, Tcl_GetString(objv[i]), " ", |
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| 188 | (char *)NULL); |
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| 189 | } |
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| 190 | specPtr = specs + n; |
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| 191 | Tcl_AppendResult(interp, specPtr->name, " ", specPtr->usage, |
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| 192 | (char *)NULL); |
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| 193 | } |
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| 194 | return NULL; |
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| 195 | } |
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| 196 | string = Tcl_GetString(objv[operPos]); |
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| 197 | if (flags & RP_OP_LINEAR_SEARCH) { |
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| 198 | n = LinearOpSearch(specs, nSpecs, string); |
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| 199 | } else { |
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| 200 | n = BinaryOpSearch(specs, nSpecs, string); |
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| 201 | } |
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| 202 | if (n == -2) { |
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| 203 | char c; |
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| 204 | size_t length; |
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| 205 | |
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| 206 | Tcl_AppendResult(interp, "ambiguous", (char *)NULL); |
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| 207 | if (operPos > 2) { |
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| 208 | Tcl_AppendResult(interp, " ", Tcl_GetString(objv[operPos - 1]), |
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| 209 | (char *)NULL); |
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| 210 | } |
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| 211 | Tcl_AppendResult(interp, " operation \"", string, "\" matches: ", |
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| 212 | (char *)NULL); |
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| 213 | |
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| 214 | c = string[0]; |
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| 215 | length = strlen(string); |
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| 216 | for (n = 0; n < nSpecs; n++) { |
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| 217 | specPtr = specs + n; |
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| 218 | if ((c == specPtr->name[0]) && |
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| 219 | (strncmp(string, specPtr->name, length) == 0)) { |
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| 220 | Tcl_AppendResult(interp, " ", specPtr->name, (char *)NULL); |
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| 221 | } |
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| 222 | } |
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| 223 | return NULL; |
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| 224 | |
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| 225 | } else if (n == -1) { /* Can't find operation, display help */ |
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| 226 | Tcl_AppendResult(interp, "bad", (char *)NULL); |
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| 227 | if (operPos > 2) { |
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| 228 | Tcl_AppendResult(interp, " ", Tcl_GetString(objv[operPos - 1]), |
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| 229 | (char *)NULL); |
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| 230 | } |
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| 231 | Tcl_AppendResult(interp, " operation \"", string, "\": ", (char *)NULL); |
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| 232 | goto usage; |
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| 233 | } |
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| 234 | specPtr = specs + n; |
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| 235 | if ((objc < specPtr->minArgs) || |
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| 236 | ((specPtr->maxArgs > 0) && (objc > specPtr->maxArgs))) { |
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| 237 | int i; |
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| 238 | |
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| 239 | Tcl_AppendResult(interp, "wrong # args: should be \"", (char *)NULL); |
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| 240 | for (i = 0; i < operPos; i++) { |
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| 241 | Tcl_AppendResult(interp, Tcl_GetString(objv[i]), " ", |
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| 242 | (char *)NULL); |
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| 243 | } |
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| 244 | Tcl_AppendResult(interp, specPtr->name, " ", specPtr->usage, "\"", |
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| 245 | (char *)NULL); |
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| 246 | return NULL; |
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| 247 | } |
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| 248 | return specPtr->proc; |
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| 249 | } |
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