| | 1 | | using System; |
| | 2 | | using System.Collections; |
| | 3 | | using System.Text; |
| | 4 | | using System.Text.RegularExpressions; |
| | 5 | |
|
| | 6 | | namespace ICSharpCode.SharpZipLib.Core |
| | 7 | | { |
| | 8 | | /// <summary> |
| | 9 | | /// NameFilter is a string matching class which allows for both positive and negative |
| | 10 | | /// matching. |
| | 11 | | /// A filter is a sequence of independant <see cref="Regex">regular expressions</see> separated by semi-colons ';'. |
| | 12 | | /// To include a semi-colon it may be quoted as in \;. Each expression can be prefixed by a plus '+' sign or |
| | 13 | | /// a minus '-' sign to denote the expression is intended to include or exclude names. |
| | 14 | | /// If neither a plus or minus sign is found include is the default. |
| | 15 | | /// A given name is tested for inclusion before checking exclusions. Only names matching an include spec |
| | 16 | | /// and not matching an exclude spec are deemed to match the filter. |
| | 17 | | /// An empty filter matches any name. |
| | 18 | | /// </summary> |
| | 19 | | /// <example>The following expression includes all name ending in '.dat' with the exception of 'dummy.dat' |
| | 20 | | /// "+\.dat$;-^dummy\.dat$" |
| | 21 | | /// </example> |
| | 22 | | public class NameFilter : IScanFilter |
| | 23 | | { |
| | 24 | | #region Constructors |
| | 25 | | /// <summary> |
| | 26 | | /// Construct an instance based on the filter expression passed |
| | 27 | | /// </summary> |
| | 28 | | /// <param name="filter">The filter expression.</param> |
| 11 | 29 | | public NameFilter(string filter) |
| | 30 | | { |
| 11 | 31 | | filter_ = filter; |
| 11 | 32 | | inclusions_ = new ArrayList(); |
| 11 | 33 | | exclusions_ = new ArrayList(); |
| 11 | 34 | | Compile(); |
| 11 | 35 | | } |
| | 36 | | #endregion |
| | 37 | |
|
| | 38 | | /// <summary> |
| | 39 | | /// Test a string to see if it is a valid regular expression. |
| | 40 | | /// </summary> |
| | 41 | | /// <param name="expression">The expression to test.</param> |
| | 42 | | /// <returns>True if expression is a valid <see cref="System.Text.RegularExpressions.Regex"/> false otherwise.</retu |
| | 43 | | public static bool IsValidExpression(string expression) |
| | 44 | | { |
| 0 | 45 | | bool result = true; |
| | 46 | | try { |
| 0 | 47 | | var exp = new Regex(expression, RegexOptions.IgnoreCase | RegexOptions.Singleline); |
| 0 | 48 | | } catch (ArgumentException) { |
| 0 | 49 | | result = false; |
| 0 | 50 | | } |
| 0 | 51 | | return result; |
| | 52 | | } |
| | 53 | |
|
| | 54 | | /// <summary> |
| | 55 | | /// Test an expression to see if it is valid as a filter. |
| | 56 | | /// </summary> |
| | 57 | | /// <param name="toTest">The filter expression to test.</param> |
| | 58 | | /// <returns>True if the expression is valid, false otherwise.</returns> |
| | 59 | | public static bool IsValidFilterExpression(string toTest) |
| | 60 | | { |
| 5 | 61 | | bool result = true; |
| | 62 | |
|
| | 63 | | try { |
| 5 | 64 | | if (toTest != null) { |
| 4 | 65 | | string[] items = SplitQuoted(toTest); |
| 10 | 66 | | for (int i = 0; i < items.Length; ++i) { |
| 3 | 67 | | if ((items[i] != null) && (items[i].Length > 0)) { |
| | 68 | | string toCompile; |
| | 69 | |
|
| 3 | 70 | | if (items[i][0] == '+') { |
| 0 | 71 | | toCompile = items[i].Substring(1, items[i].Length - 1); |
| 3 | 72 | | } else if (items[i][0] == '-') { |
| 0 | 73 | | toCompile = items[i].Substring(1, items[i].Length - 1); |
| 0 | 74 | | } else { |
| 3 | 75 | | toCompile = items[i]; |
| | 76 | | } |
| | 77 | |
|
| 3 | 78 | | var testRegex = new Regex(toCompile, RegexOptions.IgnoreCase | RegexOptions.Singleline); |
| | 79 | | } |
| | 80 | | } |
| | 81 | | } |
| 5 | 82 | | } catch (ArgumentException) { |
| 2 | 83 | | result = false; |
| 2 | 84 | | } |
| | 85 | |
|
| 5 | 86 | | return result; |
| | 87 | | } |
| | 88 | |
|
| | 89 | | /// <summary> |
| | 90 | | /// Split a string into its component pieces |
| | 91 | | /// </summary> |
| | 92 | | /// <param name="original">The original string</param> |
| | 93 | | /// <returns>Returns an array of <see cref="T:System.String"/> values containing the individual filter elements.</re |
| | 94 | | public static string[] SplitQuoted(string original) |
| | 95 | | { |
| 13 | 96 | | char escape = '\\'; |
| 13 | 97 | | char[] separators = { ';' }; |
| | 98 | |
|
| 13 | 99 | | var result = new ArrayList(); |
| | 100 | |
|
| 13 | 101 | | if (!string.IsNullOrEmpty(original)) { |
| 11 | 102 | | int endIndex = -1; |
| 11 | 103 | | var b = new StringBuilder(); |
| | 104 | |
|
| 78 | 105 | | while (endIndex < original.Length) { |
| 67 | 106 | | endIndex += 1; |
| 67 | 107 | | if (endIndex >= original.Length) { |
| 11 | 108 | | result.Add(b.ToString()); |
| 67 | 109 | | } else if (original[endIndex] == escape) { |
| 11 | 110 | | endIndex += 1; |
| 11 | 111 | | if (endIndex >= original.Length) { |
| 0 | 112 | | throw new ArgumentException("Missing terminating escape character", nameof(original)); |
| | 113 | | } |
| | 114 | | // include escape if this is not an escaped separator |
| 11 | 115 | | if (Array.IndexOf(separators, original[endIndex]) < 0) |
| 6 | 116 | | b.Append(escape); |
| | 117 | |
|
| 11 | 118 | | b.Append(original[endIndex]); |
| 11 | 119 | | } else { |
| 45 | 120 | | if (Array.IndexOf(separators, original[endIndex]) >= 0) { |
| 11 | 121 | | result.Add(b.ToString()); |
| 11 | 122 | | b.Length = 0; |
| 11 | 123 | | } else { |
| 34 | 124 | | b.Append(original[endIndex]); |
| | 125 | | } |
| | 126 | | } |
| | 127 | | } |
| | 128 | | } |
| | 129 | |
|
| 13 | 130 | | return (string[])result.ToArray(typeof(string)); |
| | 131 | | } |
| | 132 | |
|
| | 133 | | /// <summary> |
| | 134 | | /// Convert this filter to its string equivalent. |
| | 135 | | /// </summary> |
| | 136 | | /// <returns>The string equivalent for this filter.</returns> |
| | 137 | | public override string ToString() |
| | 138 | | { |
| 0 | 139 | | return filter_; |
| | 140 | | } |
| | 141 | |
|
| | 142 | | /// <summary> |
| | 143 | | /// Test a value to see if it is included by the filter. |
| | 144 | | /// </summary> |
| | 145 | | /// <param name="name">The value to test.</param> |
| | 146 | | /// <returns>True if the value is included, false otherwise.</returns> |
| | 147 | | public bool IsIncluded(string name) |
| | 148 | | { |
| 14149 | 149 | | bool result = false; |
| 14149 | 150 | | if (inclusions_.Count == 0) { |
| 2 | 151 | | result = true; |
| 2 | 152 | | } else { |
| 56584 | 153 | | foreach (Regex r in inclusions_) { |
| 14147 | 154 | | if (r.IsMatch(name)) { |
| 4 | 155 | | result = true; |
| 4 | 156 | | break; |
| | 157 | | } |
| | 158 | | } |
| | 159 | | } |
| 14149 | 160 | | return result; |
| | 161 | | } |
| | 162 | |
|
| | 163 | | /// <summary> |
| | 164 | | /// Test a value to see if it is excluded by the filter. |
| | 165 | | /// </summary> |
| | 166 | | /// <param name="name">The value to test.</param> |
| | 167 | | /// <returns>True if the value is excluded, false otherwise.</returns> |
| | 168 | | public bool IsExcluded(string name) |
| | 169 | | { |
| 5 | 170 | | bool result = false; |
| 10 | 171 | | foreach (Regex r in exclusions_) { |
| 0 | 172 | | if (r.IsMatch(name)) { |
| 0 | 173 | | result = true; |
| 0 | 174 | | break; |
| | 175 | | } |
| | 176 | | } |
| 5 | 177 | | return result; |
| | 178 | | } |
| | 179 | |
|
| | 180 | | #region IScanFilter Members |
| | 181 | | /// <summary> |
| | 182 | | /// Test a value to see if it matches the filter. |
| | 183 | | /// </summary> |
| | 184 | | /// <param name="name">The value to test.</param> |
| | 185 | | /// <returns>True if the value matches, false otherwise.</returns> |
| | 186 | | public bool IsMatch(string name) |
| | 187 | | { |
| 14148 | 188 | | return (IsIncluded(name) && !IsExcluded(name)); |
| | 189 | | } |
| | 190 | | #endregion |
| | 191 | |
|
| | 192 | | /// <summary> |
| | 193 | | /// Compile this filter. |
| | 194 | | /// </summary> |
| | 195 | | void Compile() |
| | 196 | | { |
| | 197 | | // TODO: Check to see if combining RE's makes it faster/smaller. |
| | 198 | | // simple scheme would be to have one RE for inclusion and one for exclusion. |
| 11 | 199 | | if (filter_ == null) { |
| 6 | 200 | | return; |
| | 201 | | } |
| | 202 | |
|
| 5 | 203 | | string[] items = SplitQuoted(filter_); |
| 20 | 204 | | for (int i = 0; i < items.Length; ++i) { |
| 5 | 205 | | if ((items[i] != null) && (items[i].Length > 0)) { |
| 5 | 206 | | bool include = (items[i][0] != '-'); |
| | 207 | | string toCompile; |
| | 208 | |
|
| 5 | 209 | | if (items[i][0] == '+') { |
| 0 | 210 | | toCompile = items[i].Substring(1, items[i].Length - 1); |
| 5 | 211 | | } else if (items[i][0] == '-') { |
| 0 | 212 | | toCompile = items[i].Substring(1, items[i].Length - 1); |
| 0 | 213 | | } else { |
| 5 | 214 | | toCompile = items[i]; |
| | 215 | | } |
| | 216 | |
|
| | 217 | | // NOTE: Regular expressions can fail to compile here for a number of reasons that cause an exception |
| | 218 | | // these are left unhandled here as the caller is responsible for ensuring all is valid. |
| | 219 | | // several functions IsValidFilterExpression and IsValidExpression are provided for such checking |
| 5 | 220 | | if (include) { |
| 5 | 221 | | inclusions_.Add(new Regex(toCompile, RegexOptions.IgnoreCase | RegexOptions.Compiled | RegexOptions.Singleli |
| 5 | 222 | | } else { |
| 0 | 223 | | exclusions_.Add(new Regex(toCompile, RegexOptions.IgnoreCase | RegexOptions.Compiled | RegexOptions.Singleli |
| | 224 | | } |
| | 225 | | } |
| | 226 | | } |
| 5 | 227 | | } |
| | 228 | |
|
| | 229 | | #region Instance Fields |
| | 230 | | string filter_; |
| | 231 | | ArrayList inclusions_; |
| | 232 | | ArrayList exclusions_; |
| | 233 | | #endregion |
| | 234 | | } |
| | 235 | | } |