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TW-TS-005 reader: fix maximum line length bug TW-TS-005 section 4.1 states: The maximum allowed length of each line is 80 characters, not including the OS-specific newline encoding. The implementation of this line length limit in the TW-TS-005 hex file reader function in the present suite was wrong, such that lines of the full maximum length could not be read. Fix it. Note that this bug affects comment lines too, not just actual RTP payloads. Neither Annex A nor Annex B features an RTP payload format that goes to the maximum of 40 bytes, but if a comment line goes to the maximum allowed length of 80 characters not including the terminating newline, the bug will be triggered, necessitating the present fix.
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 25 Feb 2025 07:49:28 +0000
parents 3da7ab45910d
children
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1 /*****************************************************************************
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2 * *
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3 * This file contains operations in double precision. *
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4 * These operations are not standard double precision operations. *
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5 * They are used where single precision is not enough but the full 32 bits *
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6 * precision is not necessary. For example, the function Div_32() has a *
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7 * 24 bits precision which is enough for our purposes. *
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8 * *
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9 * The double precision numbers use a special representation: *
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10 * *
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11 * L_32 = hi<<16 + lo<<1 *
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12 * *
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13 * L_32 is a 32 bit integer. *
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14 * hi and lo are 16 bit signed integers. *
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15 * As the low part also contains the sign, this allows fast multiplication. *
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16 * *
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17 * 0x8000 0000 <= L_32 <= 0x7fff fffe. *
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18 * *
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19 * We will use DPF (Double Precision Format )in this file to specify *
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20 * this special format. *
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21 *****************************************************************************
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22 */
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23
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24 #include "gsm_efr.h"
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25 #include "typedef.h"
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26 #include "namespace.h"
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27 #include "basic_op.h"
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28 #include "oper_32b.h"
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29 #include "no_count.h"
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30
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31 /*****************************************************************************
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32 * Function Mpy_32() *
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33 * *
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34 * Multiply two 32 bit integers (DPF). The result is divided by 2**31 *
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35 * *
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36 * L_32 = (hi1*hi2)<<1 + ( (hi1*lo2)>>15 + (lo1*hi2)>>15 )<<1 *
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37 * *
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38 * This operation can also be viewed as the multiplication of two Q31 *
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39 * number and the result is also in Q31. *
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40 * *
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41 * Arguments: *
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42 * *
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43 * hi1 hi part of first number *
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44 * lo1 lo part of first number *
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45 * hi2 hi part of second number *
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46 * lo2 lo part of second number *
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47 * *
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48 *****************************************************************************
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49 */
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50
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51 Word32 Mpy_32 (Word16 hi1, Word16 lo1, Word16 hi2, Word16 lo2)
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52 {
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53 Word32 L_32;
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54
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55 L_32 = L_mult (hi1, hi2);
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56 L_32 = L_mac (L_32, mult (hi1, lo2), 1);
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57 L_32 = L_mac (L_32, mult (lo1, hi2), 1);
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58
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59 return (L_32);
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60 }
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61
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62 /*****************************************************************************
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63 * Function Mpy_32_16() *
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64 * *
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65 * Multiply a 16 bit integer by a 32 bit (DPF). The result is divided *
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66 * by 2**15 *
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67 * *
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68 * *
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69 * L_32 = (hi1*lo2)<<1 + ((lo1*lo2)>>15)<<1 *
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70 * *
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71 * Arguments: *
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72 * *
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73 * hi hi part of 32 bit number. *
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74 * lo lo part of 32 bit number. *
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75 * n 16 bit number. *
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76 * *
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77 *****************************************************************************
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78 */
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79
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80 Word32 Mpy_32_16 (Word16 hi, Word16 lo, Word16 n)
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81 {
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82 Word32 L_32;
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83
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84 L_32 = L_mult (hi, n);
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85 L_32 = L_mac (L_32, mult (lo, n), 1);
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86
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87 return (L_32);
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88 }
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89
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90 /*****************************************************************************
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91 * *
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92 * Function Name : Div_32 *
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93 * *
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94 * Purpose : *
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95 * Fractional integer division of two 32 bit numbers. *
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96 * L_num / L_denom. *
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97 * L_num and L_denom must be positive and L_num < L_denom. *
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98 * L_denom = denom_hi<<16 + denom_lo<<1 *
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99 * denom_hi is a normalize number. *
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100 * *
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101 * Inputs : *
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102 * *
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103 * L_num *
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104 * 32 bit long signed integer (Word32) whose value falls in the *
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105 * range : 0x0000 0000 < L_num < L_denom *
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106 * *
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107 * L_denom = denom_hi<<16 + denom_lo<<1 (DPF) *
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108 * *
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109 * denom_hi *
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110 * 16 bit positive normalized integer whose value falls in the *
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111 * range : 0x4000 < hi < 0x7fff *
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112 * denom_lo *
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113 * 16 bit positive integer whose value falls in the *
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114 * range : 0 < lo < 0x7fff *
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115 * *
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116 * Return Value : *
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117 * *
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118 * L_div *
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119 * 32 bit long signed integer (Word32) whose value falls in the *
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120 * range : 0x0000 0000 <= L_div <= 0x7fff ffff. *
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121 * *
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122 * Algorithm: *
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123 * *
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124 * - find = 1/L_denom. *
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125 * First approximation: approx = 1 / denom_hi *
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126 * 1/L_denom = approx * (2.0 - L_denom * approx ) *
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127 * *
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128 * - result = L_num * (1/L_denom) *
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129 *****************************************************************************
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130 */
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131
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132 Word32 Div_32 (Word32 L_num, Word16 denom_hi, Word16 denom_lo)
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133 {
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134 Word16 approx, hi, lo, n_hi, n_lo;
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135 Word32 L_32;
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136
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137 /* First approximation: 1 / L_denom = 1/denom_hi */
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138
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139 approx = div_s ((Word16) 0x3fff, denom_hi);
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140
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141 /* 1/L_denom = approx * (2.0 - L_denom * approx) */
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142
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143 L_32 = Mpy_32_16 (denom_hi, denom_lo, approx);
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144
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145 L_32 = L_sub ((Word32) 0x7fffffffL, L_32);
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146
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147 L_Extract (L_32, &hi, &lo);
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148
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149 L_32 = Mpy_32_16 (hi, lo, approx);
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150
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151 /* L_num * (1/L_denom) */
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152
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153 L_Extract (L_32, &hi, &lo);
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154 L_Extract (L_num, &n_hi, &n_lo);
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155 L_32 = Mpy_32 (n_hi, n_lo, hi, lo);
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156 L_32 = L_shl (L_32, 2);
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157
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158 return (L_32);
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159 }