2008-11-05 Steve Bennett <steveb@workware.net.au>

	* jim-regexp.c: Add regexp extension for regexp and regsub commands

1 files changed, 482 insertions, 0 deletions

diff --git a/jim-regexp.c b/jim-regexp.c
new file mode 100644
index 0000000..72d2f1f
--- /dev/null
+++ b/jim-regexp.c
@@ -0,0 +1,482 @@
+/* 

+ * (c) 2008 Steve Bennett <steveb@workware.net.au>

+ *

+ * Implements the regexp and regsub commands for Jim

+ *

+ * Uses C library regcomp()/regexec() for the matching.

+ *

+ * The FreeBSD license

+ * 

+ * Redistribution and use in source and binary forms, with or without

+ * modification, are permitted provided that the following conditions

+ * are met:

+ * 

+ * 1. Redistributions of source code must retain the above copyright

+ *    notice, this list of conditions and the following disclaimer.

+ * 2. Redistributions in binary form must reproduce the above

+ *    copyright notice, this list of conditions and the following

+ *    disclaimer in the documentation and/or other materials

+ *    provided with the distribution.

+ * 

+ * THIS SOFTWARE IS PROVIDED BY THE JIM TCL PROJECT ``AS IS'' AND ANY

+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A

+ * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE

+ * JIM TCL PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,

+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF

+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

+ * 

+ * The views and conclusions contained in the software and documentation

+ * are those of the authors and should not be interpreted as representing

+ * official policies, either expressed or implied, of the Jim Tcl Project.

+ *

+ * Based on code originally from Tcl 6.7:

+ *

+ * Copyright 1987-1991 Regents of the University of California

+ * Permission to use, copy, modify, and distribute this

+ * software and its documentation for any purpose and without

+ * fee is hereby granted, provided that the above copyright

+ * notice appear in all copies.  The University of California

+ * makes no representations about the suitability of this

+ * software for any purpose.  It is provided "as is" without

+ * express or implied warranty.

+ */

+

+#include <regex.h>

+#include <string.h>

+

+#define JIM_EXTENSION

+#include "jim.h"

+

+/* REVISIT: Would be useful in jim.h */

+static void Jim_SetIntResult(Jim_Interp *interp, jim_wide wide)

+{

+    Jim_SetResult(interp, Jim_NewIntObj(interp, wide));

+}

+

+/**

+ * REVISIT: Should cache a number of compiled regexps for performance reasons.

+ */

+static regex_t * 

+compile_regexp(Jim_Interp *interp, const char *pattern, int flags)

+{

+    int ret;

+

+    regex_t *result = (regex_t *)Jim_Alloc(sizeof(*result));

+

+    if ((ret = regcomp(result, pattern, REG_EXTENDED | flags)) != 0) {

+        char buf[100];

+        regerror(ret, result, buf, sizeof(buf));

+        Jim_SetResult(interp, Jim_NewEmptyStringObj(interp));

+        Jim_AppendStrings(interp, Jim_GetResult(interp), "couldn't compile regular expression pattern: ", buf, NULL);

+        Jim_Free(result);

+        return NULL;

+    }

+    return result;

+}

+

+int Jim_RegexpCmd(Jim_Interp *interp, int argc, Jim_Obj *const *argv)

+{

+    int opt_indices = 0;

+    int opt_all = 0;

+    int opt_inline = 0;

+    regex_t *regex;

+    int match, i, j;

+    long offset = 0;

+    regmatch_t *pmatch = NULL;

+    int source_len;

+    int result = JIM_OK;

+    const char *pattern;

+    const char *source_str;

+    int num_matches = 0;

+    int num_vars;

+    Jim_Obj *resultListObj = NULL;

+    int regcomp_flags = 0;

+

+    if (argc < 3) {

+        wrongNumArgs:

+        Jim_WrongNumArgs(interp, 1, argv, "?-nocase? ?-line? ?-indices? ?-start offset? ?-all? ?-inline? exp string ?matchVar? ?subMatchVar ...?");

+        return JIM_ERR;

+    }

+

+    for (i = 1; i < argc; i++) {

+        if (Jim_CompareStringImmediate(interp, argv[i], "-indices")) {

+            opt_indices = 1;

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "-nocase")) {

+            regcomp_flags |= REG_ICASE;

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "-line")) {

+            regcomp_flags |= REG_NEWLINE;

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "-all")) {

+            opt_all = 1;

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "-inline")) {

+            opt_inline = 1;

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "-start")) {

+            if (++i == argc) {

+                goto wrongNumArgs;

+            }

+            if (Jim_GetLong(interp, argv[i], &offset) != JIM_OK) {

+                return JIM_ERR;

+            }

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "--")) {

+            i++;

+            break;

+        }

+        else {

+            const char *opt = Jim_GetString(argv[i], NULL);

+            if (*opt == '-') {

+                /* Bad option */

+                goto wrongNumArgs;

+            }

+            break;

+        }

+    }

+    if (argc - i < 2) {

+        goto wrongNumArgs;

+    }

+

+    pattern = Jim_GetString(argv[i], NULL);

+    regex = compile_regexp(interp, pattern, regcomp_flags);

+    if (regex == NULL) {

+        return JIM_ERR;

+    }

+

+    source_str = Jim_GetString(argv[i + 1], &source_len);

+

+    num_vars = argc - i - 2;

+

+    if (opt_inline) {

+        if (num_vars) {

+            Jim_SetResultString(interp, "regexp match variables not allowed when using -inline", -1);

+            result = JIM_ERR;

+            goto done;

+        }

+        /* REVISIT: Ugly! */

+        num_vars = 100;

+    }

+

+    pmatch = Jim_Alloc((num_vars + 1) * sizeof(*pmatch));

+

+    /* If an offset has been specified, adjust for that now.

+     * If it points past the end of the string, point to the terminating null

+     */

+    if (offset) {

+        if (offset > source_len) {

+            source_str += source_len;

+        } else if (offset > 0) {

+            source_str += offset;

+        }

+    }

+

+    if (opt_inline) {

+        resultListObj = Jim_NewListObj(interp, NULL, 0);

+    }

+

+    next_match:

+    match = regexec(regex, source_str, num_vars + 1, pmatch, 0);

+    if (match >= REG_BADPAT) {

+        char buf[100];

+        regerror(match, regex, buf, sizeof(buf));

+        Jim_SetResultString(interp, "", 0);

+        Jim_AppendStrings(interp, Jim_GetResult(interp), "error while matching pattern: ", buf, NULL);

+        result = JIM_ERR;

+        goto done;

+    }

+

+    if (match == REG_NOMATCH) {

+        goto done;

+    }

+

+    num_matches++;

+

+    if (opt_all && !opt_inline) {

+        /* Just count the number of matches, so skip the substitution h*/

+        goto try_next_match;

+    }

+

+    /*

+     * If additional variable names have been specified, return

+     * index information in those variables.

+     */

+

+    //fprintf(stderr, "source_str=%s, [0].rm_eo=%d\n", source_str, pmatch[0].rm_eo);

+

+    j = 0;

+    for (i += 2; opt_inline ? pmatch[j].rm_so != -1 : i < argc; i++, j++) {

+        Jim_Obj *resultObj;

+

+        if (opt_indices) {

+            resultObj = Jim_NewListObj(interp, NULL, 0);

+        }

+        else {

+            resultObj = Jim_NewStringObj(interp, "", 0);

+        }

+

+        if (pmatch[j].rm_so == -1) {

+            if (opt_indices) {

+                Jim_ListAppendElement(interp, resultObj, Jim_NewIntObj(interp, -1));

+                Jim_ListAppendElement(interp, resultObj, Jim_NewIntObj(interp, -1));

+            }

+        } else {

+            int len = pmatch[j].rm_eo - pmatch[j].rm_so;

+            if (opt_indices) {

+                Jim_ListAppendElement(interp, resultObj, Jim_NewIntObj(interp, offset + pmatch[j].rm_so));

+                Jim_ListAppendElement(interp, resultObj, Jim_NewIntObj(interp, offset + pmatch[j].rm_so + len - 1));

+            } else {

+                Jim_AppendString(interp, resultObj, source_str + pmatch[j].rm_so, len);

+            }

+        }

+

+        if (opt_inline) {

+            Jim_ListAppendElement(interp, resultListObj, resultObj);

+        }

+        else {

+            /* And now set the result variable */

+            result = Jim_SetVariable(interp, argv[i], resultObj);

+

+            if (result != JIM_OK) {

+                Jim_SetResult(interp, Jim_NewEmptyStringObj(interp));

+                Jim_AppendStrings(interp, Jim_GetResult(interp), "couldn't set variable \"", Jim_GetString(argv[i], NULL), "\"", NULL);

+                Jim_FreeObj(interp, resultObj);

+                break;

+            }

+        }

+    }

+

+    try_next_match:

+    if (opt_all && pattern[0] != '^' && *source_str) {

+        if (pmatch[0].rm_eo) {

+            source_str += pmatch[0].rm_eo;

+        }

+        else {

+            source_str++;

+        }

+        if (*source_str) {

+            goto next_match;

+        }

+    }

+

+    done:

+    if (result == JIM_OK) {

+        if (opt_inline) {

+            Jim_SetResult(interp, resultListObj);

+        }

+        else {

+            Jim_SetIntResult(interp, num_matches);

+        }

+    }

+

+    Jim_Free(pmatch);

+    regfree(regex);

+    Jim_Free(regex);

+    return result;

+}

+

+#define MAX_SUB_MATCHES 10

+

+int Jim_RegsubCmd(Jim_Interp *interp, int argc, Jim_Obj *const *argv)

+{

+    int regcomp_flags = 0;

+    int opt_all = 0;

+    long offset = 0;

+    regex_t *regex;

+    const char *p;

+    int result = JIM_ERR;

+    regmatch_t pmatch[MAX_SUB_MATCHES + 1];

+    int num_matches = 0;

+

+    int i;

+    Jim_Obj *varname;

+    Jim_Obj *resultObj;

+    const char *source_str;

+    int source_len;

+    const char *replace_str;

+    const char *pattern;

+

+    if (argc < 5) {

+        wrongNumArgs:

+        Jim_WrongNumArgs(interp, 1, argv, "?-nocase? ?-all? exp string subSpec varName");

+        return JIM_ERR;

+    }

+

+    for (i = 1; i < argc; i++) {

+        if (Jim_CompareStringImmediate(interp, argv[i], "-nocase")) {

+            regcomp_flags |= REG_ICASE;

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "-line")) {

+            regcomp_flags |= REG_NEWLINE;

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "-all")) {

+            opt_all = 1;

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "-start")) {

+            if (++i == argc) {

+                goto wrongNumArgs;

+            }

+            if (Jim_GetLong(interp, argv[i], &offset) != JIM_OK) {

+                return JIM_ERR;

+            }

+        }

+        else if (Jim_CompareStringImmediate(interp, argv[i], "--")) {

+            i++;

+            break;

+        }

+        else {

+            const char *opt = Jim_GetString(argv[i], NULL);

+            if (*opt == '-') {

+                /* Bad option */

+                goto wrongNumArgs;

+            }

+            break;

+        }

+    }

+    if (argc - i != 4) {

+        goto wrongNumArgs;

+    }

+

+    pattern = Jim_GetString(argv[i], NULL);

+    regex = compile_regexp(interp, pattern, regcomp_flags);

+    if (regex == NULL) {

+        return JIM_ERR;

+    }

+

+    source_str = Jim_GetString(argv[i + 1], &source_len);

+    replace_str = Jim_GetString(argv[i + 2], NULL);

+    varname = argv[i + 3];

+

+    /* Create the result string */

+    resultObj = Jim_NewStringObj(interp, "", 0);

+

+    /* If an offset has been specified, adjust for that now.

+     * If it points past the end of the string, point to the terminating null

+     */

+    if (offset) {

+        if (offset > source_len) {

+            offset = source_len;

+        } else if (offset < 0) {

+            offset = 0;

+        }

+    }

+

+    /* Copy the part before -start */

+    Jim_AppendString(interp, resultObj, source_str, offset);

+

+    /*

+     * The following loop is to handle multiple matches within the

+     * same source string;  each iteration handles one match and its

+     * corresponding substitution.  If "-all" hasn't been specified

+     * then the loop body only gets executed once.

+     */

+

+    for (p = source_str + offset; *p != 0; ) {

+        const char *src;

+        int match = regexec(regex, p, MAX_SUB_MATCHES, pmatch, 0);

+        if (match >= REG_BADPAT) {

+            char buf[100];

+            regerror(match, regex, buf, sizeof(buf));

+            Jim_SetResultString(interp, "", 0);

+            Jim_AppendStrings(interp, Jim_GetResult(interp), "error while matching pattern: ", buf, NULL);

+            goto done;

+        }

+        if (match == REG_NOMATCH) {

+            break;

+        }

+

+        num_matches++;

+

+        /*

+         * Copy the portion of the source string before the match to the

+         * result variable.

+         */

+        Jim_AppendString(interp, resultObj, p, pmatch[0].rm_so);

+

+        /*

+         * Append the subSpec (replace_str) argument to the variable, making appropriate

+         * substitutions.  This code is a bit hairy because of the backslash

+         * conventions and because the code saves up ranges of characters in

+         * subSpec to reduce the number of calls to Jim_SetVar.

+         */

+    

+        for (src = replace_str; *src; src++) {

+            int index;

+            int c = *src;

+

+            if (c == '&') {

+                index = 0;

+            }

+            else if (c == '\\') {

+                c = *++src;

+                if ((c >= '0') && (c <= '9')) {

+                    index = c - '0';

+                }

+                else if ((c == '\\') || (c == '&')) {

+                    Jim_AppendString(interp, resultObj, src, 1);

+                    continue;

+                }

+                else {

+                    Jim_AppendString(interp, resultObj, src - 1, 2);

+                    continue;

+                }

+            }

+            else {

+                Jim_AppendString(interp, resultObj, src, 1);

+                continue;

+            }

+            if ((index < MAX_SUB_MATCHES) && pmatch[index].rm_so != -1 && pmatch[index].rm_eo != -1) {

+                Jim_AppendString(interp, resultObj, p + pmatch[index].rm_so, pmatch[index].rm_eo - pmatch[index].rm_so);

+            }

+        }

+

+        p += pmatch[0].rm_eo;

+

+        if (!opt_all || pmatch[0].rm_eo == 0 || pattern[0] == '^') {

+            /* If we are doing a single match, or we haven't moved with this match

+             * or this is an anchored match, we stop */

+            break;

+        }

+    }

+

+    /*

+     * Copy the portion of the string after the last match to the

+     * result variable.

+     */

+    Jim_AppendString(interp, resultObj, p, -1);

+

+    /* And now set the result variable */

+    result = Jim_SetVariable(interp, varname, resultObj);

+

+    if (result == JIM_OK) {

+        Jim_SetIntResult(interp, num_matches);

+    }

+    else {

+        Jim_SetResult(interp, Jim_NewEmptyStringObj(interp));

+        Jim_AppendStrings(interp, Jim_GetResult(interp), "couldn't set variable \"", Jim_GetString(varname, NULL), "\"", NULL);

+        Jim_FreeObj(interp, resultObj);

+    }

+

+    done:

+    regfree(regex);

+    Jim_Free(regex);

+    return result;

+}

+

+int Jim_OnLoad(Jim_Interp *interp)

+{

+        Jim_InitExtension(interp);

+        if (Jim_PackageProvide(interp, "regexp", "1.0", JIM_ERRMSG) != JIM_OK) {

+                return JIM_ERR;

+        }

+        Jim_CreateCommand(interp, "regexp", Jim_RegexpCmd, NULL, NULL);

+        Jim_CreateCommand(interp, "regsub", Jim_RegsubCmd, NULL, NULL);

+        return JIM_OK;

+}