summaryrefslogtreecommitdiffstats
path: root/libtecla-1.4.1/history.c
diff options
context:
space:
mode:
Diffstat (limited to 'libtecla-1.4.1/history.c')
-rw-r--r--libtecla-1.4.1/history.c2003
1 files changed, 0 insertions, 2003 deletions
diff --git a/libtecla-1.4.1/history.c b/libtecla-1.4.1/history.c
deleted file mode 100644
index 5a8d94f..0000000
--- a/libtecla-1.4.1/history.c
+++ /dev/null
@@ -1,2003 +0,0 @@
-/*
- * Copyright (c) 2000, 2001 by Martin C. Shepherd.
- *
- * All rights reserved.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the
- * "Software"), to deal in the Software without restriction, including
- * without limitation the rights to use, copy, modify, merge, publish,
- * distribute, and/or sell copies of the Software, and to permit persons
- * to whom the Software is furnished to do so, provided that the above
- * copyright notice(s) and this permission notice appear in all copies of
- * the Software and that both the above copyright notice(s) and this
- * permission notice appear in supporting documentation.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
- * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
- * OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
- * HOLDERS INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL
- * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING
- * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
- * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
- * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- *
- * Except as contained in this notice, the name of a copyright holder
- * shall not be used in advertising or otherwise to promote the sale, use
- * or other dealings in this Software without prior written authorization
- * of the copyright holder.
- */
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <time.h>
-#include <errno.h>
-
-#include "history.h"
-#include "freelist.h"
-
-/*
- * GlLineNode's record the location and length of historical lines in
- * a buffer array.
- */
-typedef struct GlLineNode GlLineNode;
-struct GlLineNode {
- long id; /* The unique identifier of this history line */
- time_t timestamp; /* The time at which the line was archived */
- unsigned group; /* The identifier of the history group to which the */
- /* the line belongs. */
- GlLineNode *next; /* The next youngest line in the list */
- GlLineNode *prev; /* The next oldest line in the list */
- int start; /* The start index of the line in the buffer */
- int nchar; /* The total length of the line, including the '\0' */
-};
-
-/*
- * The number of GlLineNode elements per freelist block.
- */
-#define LINE_NODE_BLK 100
-
-/*
- * Lines are organised in the buffer from oldest to newest. The
- * positions of the lines are recorded in a doubly linked list
- * of GlLineNode objects.
- */
-typedef struct {
- FreeList *node_mem; /* A freelist of GlLineNode objects */
- GlLineNode *head; /* The head of the list of lines */
- GlLineNode *tail; /* The tail of the list of lines */
-} GlLineList;
-
-/*
- * All elements of the history mechanism are recorded in an object of
- * the following type.
- */
-struct GlHistory {
- char *buffer; /* A circular buffer used to record historical input */
- /* lines. */
- size_t buflen; /* The length of the buffer array */
- GlLineList list; /* A list of the start of lines in buffer[] */
- GlLineNode *recall; /* The last line recalled, or NULL if no recall */
- /* session is currently active. */
- GlLineNode *id_node;/* The node at which the last ID search terminated */
- const char *prefix; /* A pointer to the line containing the prefix that */
- /* is being searched for. */
- int prefix_len; /* The length of the prefix */
- unsigned long seq; /* The next ID to assign to a line node */
- unsigned group; /* The identifier of the current history group */
- int nline; /* The number of lines currently in the history list */
- int max_lines; /* Either -1 or a ceiling on the number of lines */
- int enable; /* If false, ignore history additions and lookups */
-};
-
-static char *_glh_restore_line(GlHistory *glh, char *line, size_t dim);
-static int _glh_cant_load_history(GlHistory *glh, const char *filename,
- int lineno, const char *message, FILE *fp);
-static int _glh_write_timestamp(FILE *fp, time_t timestamp);
-static int _glh_decode_timestamp(char *string, char **endp, time_t *t);
-static void _glh_discard_node(GlHistory *glh, GlLineNode *node);
-static GlLineNode *_glh_find_id(GlHistory *glh, GlhLineID id);
-
-/*.......................................................................
- * Create a line history maintenance object.
- *
- * Input:
- * buflen size_t The number of bytes to allocate to the circular
- * buffer that is used to record all of the
- * most recent lines of user input that will fit.
- * If buflen==0, no buffer will be allocated.
- * Output:
- * return GlHistory * The new object, or NULL on error.
- */
-GlHistory *_new_GlHistory(size_t buflen)
-{
- GlHistory *glh; /* The object to be returned */
-/*
- * Allocate the container.
- */
- glh = (GlHistory *) malloc(sizeof(GlHistory));
- if(!glh) {
- fprintf(stderr, "_new_GlHistory: Insufficient memory.\n");
- return NULL;
- };
-/*
- * Before attempting any operation that might fail, initialize the
- * container at least up to the point at which it can safely be passed
- * to _del_GlHistory().
- */
- glh->buffer = NULL;
- glh->buflen = buflen;
- glh->list.node_mem = NULL;
- glh->list.head = NULL;
- glh->list.tail = NULL;
- glh->recall = NULL;
- glh->id_node = NULL;
- glh->prefix = NULL;
- glh->prefix_len = 0;
- glh->seq = 0;
- glh->group = 0;
- glh->nline = 0;
- glh->max_lines = -1;
- glh->enable = 1;
-/*
- * Allocate the buffer, if required.
- */
- if(buflen > 0) {
- glh->buffer = (char *) malloc(sizeof(char) * buflen);
- if(!glh->buffer) {
- fprintf(stderr, "_new_GlHistory: Insufficient memory.\n");
- return _del_GlHistory(glh);
- };
- };
-/*
- * Allocate the GlLineNode freelist.
- */
- glh->list.node_mem = _new_FreeList("_new_GlHistory", sizeof(GlLineNode),
- LINE_NODE_BLK);
- if(!glh->list.node_mem)
- return _del_GlHistory(glh);
- return glh;
-}
-
-/*.......................................................................
- * Delete a GlHistory object.
- *
- * Input:
- * glh GlHistory * The object to be deleted.
- * Output:
- * return GlHistory * The deleted object (always NULL).
- */
-GlHistory *_del_GlHistory(GlHistory *glh)
-{
- if(glh) {
-/*
- * Delete the buffer.
- */
- if(glh->buffer) {
- free(glh->buffer);
- glh->buffer = NULL;
- };
-/*
- * Delete the freelist of GlLineNode's.
- */
- glh->list.node_mem = _del_FreeList("_del_GlHistory", glh->list.node_mem, 1);
-/*
- * The contents of the list were deleted by deleting the freelist.
- */
- glh->list.head = NULL;
- glh->list.tail = NULL;
-/*
- * Delete the container.
- */
- free(glh);
- };
- return NULL;
-}
-
-/*.......................................................................
- * Add a new line to the end of the history buffer, wrapping round to the
- * start of the buffer if needed.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * line char * The line to be archived.
- * force int Unless this flag is non-zero, empty lines and
- * lines which match the previous line in the history
- * buffer, aren't archived. This flag requests that
- * the line be archived regardless.
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-int _glh_add_history(GlHistory *glh, const char *line, int force)
-{
- GlLineList *list; /* The line location list */
- int nchar; /* The number of characters needed to record the line */
- GlLineNode *node; /* The new line location list node */
- int empty; /* True if the string is empty */
- const char *nlptr;/* A pointer to a newline character in line[] */
- int i;
-/*
- * Check the arguments.
- */
- if(!glh || !line)
- return 1;
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->buffer || glh->max_lines == 0)
- return 0;
-/*
- * Get the line location list.
- */
- list = &glh->list;
-/*
- * Cancel any ongoing search.
- */
- if(_glh_cancel_search(glh))
- return 1;
-/*
- * See how much buffer space will be needed to record the line?
- *
- * If the string contains a terminating newline character, arrange to
- * have the archived line NUL terminated at this point.
- */
- nlptr = strchr(line, '\n');
- if(nlptr)
- nchar = (nlptr - line) + 1;
- else
- nchar = strlen(line) + 1;
-/*
- * If the line is too big to fit in the buffer, truncate it.
- */
- if(nchar > glh->buflen)
- nchar = glh->buflen;
-/*
- * Is the line empty?
- */
- empty = 1;
- for(i=0; i<nchar-1 && empty; i++)
- empty = isspace((int)(unsigned char) line[i]);
-/*
- * If the line is empty, don't add it to the buffer unless explicitly
- * told to.
- */
- if(empty && !force)
- return 0;
-/*
- * If the new line is the same as the most recently added line,
- * don't add it again, unless explicitly told to.
- */
- if(!force &&
- list->tail && strlen(glh->buffer + list->tail->start) == nchar-1 &&
- strncmp(line, glh->buffer + list->tail->start, nchar-1)==0)
- return 0;
-/*
- * Allocate the list node that will record the line location.
- */
- node = (GlLineNode *) _new_FreeListNode(list->node_mem);
- if(!node)
- return 1;
-/*
- * Is the buffer empty?
- */
- if(!list->head) {
-/*
- * Place the line at the beginning of the buffer.
- */
- strncpy(glh->buffer, line, nchar);
- glh->buffer[nchar-1] = '\0';
-/*
- * Record the location of the line.
- */
- node->start = 0;
-/*
- * The buffer has one or more lines in it.
- */
- } else {
-/*
- * Place the start of the new line just after the most recently
- * added line.
- */
- int start = list->tail->start + list->tail->nchar;
-/*
- * If there is insufficient room between the end of the most
- * recently added line and the end of the buffer, we place the
- * line at the beginning of the buffer. To make as much space
- * as possible for this line, we first delete any old lines
- * at the end of the buffer, then shift the remaining contents
- * of the buffer to the end of the buffer.
- */
- if(start + nchar >= glh->buflen) {
- GlLineNode *last; /* The last line in the buffer */
- GlLineNode *ln; /* A member of the list of line locations */
- int shift; /* The shift needed to move the contents of the */
- /* buffer to its end. */
-/*
- * Delete any old lines between the most recent line and the end of the
- * buffer.
- */
- while(list->head && list->head->start > list->tail->start)
- _glh_discard_node(glh, list->head);
-/*
- * Find the line that is nearest the end of the buffer.
- */
- last = NULL;
- for(ln=list->head; ln; ln=ln->next) {
- if(!last || ln->start > last->start)
- last = ln;
- };
-/*
- * How big a shift is needed to move the existing contents of the
- * buffer to the end of the buffer?
- */
- shift = last ? (glh->buflen - (last->start + last->nchar)) : 0;
-/*
- * Is any shift needed?
- */
- if(shift > 0) {
-/*
- * Move the buffer contents to the end of the buffer.
- */
- memmove(glh->buffer + shift, glh->buffer, glh->buflen - shift);
-/*
- * Update the listed locations to reflect the shift.
- */
- for(ln=list->head; ln; ln=ln->next)
- ln->start += shift;
- };
-/*
- * The new line should now be located at the start of the buffer.
- */
- start = 0;
- };
-/*
- * Make space for the new line at the beginning of the buffer by
- * deleting the oldest lines. This just involves removing them
- * from the list of used locations. Also enforce the current
- * maximum number of lines.
- */
- while(list->head &&
- ((list->head->start >= start && list->head->start - start < nchar) ||
- (glh->max_lines >= 0 && glh->nline>=glh->max_lines))) {
- _glh_discard_node(glh, list->head);
- };
-/*
- * Copy the new line into the buffer.
- */
- memcpy(glh->buffer + start, line, nchar);
- glh->buffer[start + nchar - 1] = '\0';
-/*
- * Record its location.
- */
- node->start = start;
- };
-/*
- * Append the line location node to the end of the list.
- */
- node->id = glh->seq++;
- node->timestamp = time(NULL);
- node->group = glh->group;
- node->nchar = nchar;
- node->next = NULL;
- node->prev = list->tail;
- if(list->tail)
- list->tail->next = node;
- else
- list->head = node;
- list->tail = node;
- glh->nline++;
- return 0;
-}
-
-/*.......................................................................
- * Recall the next oldest line that has the search prefix last recorded
- * by _glh_search_prefix().
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * line char * The input line buffer. On input this should contain
- * the current input line, and on output, if anything
- * was found, its contents will have been replaced
- * with the matching line.
- * dim size_t The allocated dimensions of the line buffer.
- * Output:
- * return char * A pointer to line[0], or NULL if not found.
- */
-char *_glh_find_backwards(GlHistory *glh, char *line, size_t dim)
-{
- GlLineNode *node; /* The line location node being checked */
- int first; /* True if this is the start of a new search */
-/*
- * Check the arguments.
- */
- if(!glh || !line) {
- fprintf(stderr, "_glh_find_backwards: NULL argument(s).\n");
- return NULL;
- };
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->buffer || glh->max_lines == 0)
- return NULL;
-/*
- * Check the line dimensions.
- */
- if(dim < strlen(line) + 1) {
- fprintf(stderr,
- "_glh_find_backwards: 'dim' inconsistent with strlen(line) contents.\n");
- return NULL;
- };
-/*
- * Is this the start of a new search?
- */
- first = glh->recall==NULL;
-/*
- * If this is the first search backwards, save the current line
- * for potential recall later, and mark it as the last line
- * recalled.
- */
- if(first) {
- if(_glh_add_history(glh, line, 1))
- return NULL;
- glh->recall = glh->list.tail;
- };
-/*
- * If there is no search prefix, the prefix last set by glh_search_prefix()
- * doesn't exist in the history buffer.
- */
- if(!glh->prefix)
- return NULL;
-/*
- * From where should we start the search?
- */
- if(glh->recall)
- node = glh->recall->prev;
- else
- node = glh->list.tail;
-/*
- * Search backwards through the list for the first match with the
- * prefix string.
- */
- for( ; node &&
- (node->group != glh->group ||
- strncmp(glh->buffer + node->start, glh->prefix, glh->prefix_len) != 0);
- node = node->prev)
- ;
-/*
- * Was a matching line found?
- */
- if(node) {
-/*
- * Recall the found node as the starting point for subsequent
- * searches.
- */
- glh->recall = node;
-/*
- * Copy the matching line into the provided line buffer.
- */
- strncpy(line, glh->buffer + node->start, dim);
- line[dim-1] = '\0';
- return line;
- };
-/*
- * No match was found.
- */
- return NULL;
-}
-
-/*.......................................................................
- * Recall the next newest line that has the search prefix last recorded
- * by _glh_search_prefix().
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * line char * The input line buffer. On input this should contain
- * the current input line, and on output, if anything
- * was found, its contents will have been replaced
- * with the matching line.
- * dim size_t The allocated dimensions of the line buffer.
- * Output:
- * return char * The line requested, or NULL if no matching line
- * was found.
- */
-char *_glh_find_forwards(GlHistory *glh, char *line, size_t dim)
-{
- GlLineNode *node; /* The line location node being checked */
-/*
- * Check the arguments.
- */
- if(!glh || !line) {
- fprintf(stderr, "_glh_find_forwards: NULL argument(s).\n");
- return NULL;
- };
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->buffer || glh->max_lines == 0)
- return NULL;
-/*
- * Check the line dimensions.
- */
- if(dim < strlen(line) + 1) {
- fprintf(stderr,
- "_glh_find_forwards: 'dim' inconsistent with strlen(line) contents.\n");
- return NULL;
- };
-/*
- * From where should we start the search?
- */
- if(glh->recall)
- node = glh->recall->next;
- else
- return NULL;
-/*
- * If there is no search prefix, the prefix last set by glh_search_prefix()
- * doesn't exist in the history buffer.
- */
- if(!glh->prefix)
- return NULL;
-/*
- * Search forwards through the list for the first match with the
- * prefix string.
- */
- for( ; node &&
- (node->group != glh->group ||
- strncmp(glh->buffer + node->start, glh->prefix, glh->prefix_len) != 0);
- node = node->next)
- ;
-/*
- * Was a matching line found?
- */
- if(node) {
-/*
- * Did we hit the line that was originally being edited when the
- * current history traversal started?
- */
- if(node == glh->list.tail)
- return _glh_restore_line(glh, line, dim);
-/*
- * Copy the matching line into the provided line buffer.
- */
- strncpy(line, glh->buffer + node->start, dim);
- line[dim-1] = '\0';
-/*
- * Record the starting point of the next search.
- */
- glh->recall = node;
-/*
- * Return the matching line to the user.
- */
- return line;
- };
-/*
- * No match was found.
- */
- return NULL;
-}
-
-/*.......................................................................
- * If a search is in progress, cancel it.
- *
- * This involves discarding the line that was temporarily saved by
- * _glh_find_backwards() when the search was originally started,
- * and reseting the search iteration pointer to NULL.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-int _glh_cancel_search(GlHistory *glh)
-{
-/*
- * Check the arguments.
- */
- if(!glh) {
- fprintf(stderr, "_glh_cancel_search: NULL argument(s).\n");
- return 1;
- };
-/*
- * If there wasn't a search in progress, do nothing.
- */
- if(!glh->recall)
- return 0;
-/*
- * Delete the node of the preserved line.
- */
- _glh_discard_node(glh, glh->list.tail);
-/*
- * Reset the search pointers.
- */
- glh->recall = NULL;
- glh->prefix = "";
- glh->prefix_len = 0;
- return 0;
-}
-
-/*.......................................................................
- * Set the prefix of subsequent history searches.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * line char * The command line who's prefix is to be used.
- * prefix_len int The length of the prefix.
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-int _glh_search_prefix(GlHistory *glh, const char *line, int prefix_len)
-{
- GlLineNode *node; /* The line location node being checked */
-/*
- * Check the arguments.
- */
- if(!glh) {
- fprintf(stderr, "_glh_search_prefix: NULL argument(s).\n");
- return 1;
- };
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->buffer || glh->max_lines == 0)
- return 0;
-/*
- * Record a zero length search prefix?
- */
- if(prefix_len <= 0) {
- glh->prefix_len = 0;
- glh->prefix = "";
- return 0;
- };
-/*
- * Record the length of the new search prefix.
- */
- glh->prefix_len = prefix_len;
-/*
- * If any history line starts with the specified prefix, record a
- * pointer to it for comparison in subsequent searches. If the prefix
- * doesn't match any of the lines, then simply record NULL to indicate
- * that there is no point in searching. Note that _glh_add_history()
- * clears this pointer by calling _glh_cancel_search(), so there is
- * no danger of it being used after the buffer has been modified.
- */
- for(node = glh->list.tail ; node &&
- (node->group != glh->group ||
- strncmp(glh->buffer + node->start, line, prefix_len) != 0);
- node = node->prev)
- ;
-/*
- * If a matching line was found record it for use as the search
- * prefix.
- */
- glh->prefix = node ? glh->buffer + node->start : NULL;
- return 0;
-}
-
-/*.......................................................................
- * Recall the oldest recorded line.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * line char * The input line buffer. On input this should contain
- * the current input line, and on output, its contents
- * will have been replaced with the oldest line.
- * dim size_t The allocated dimensions of the line buffer.
- * Output:
- * return char * A pointer to line[0], or NULL if not found.
- */
-char *_glh_oldest_line(GlHistory *glh, char *line, size_t dim)
-{
- GlLineNode *node; /* The line location node being checked */
- int first; /* True if this is the start of a new search */
-/*
- * Check the arguments.
- */
- if(!glh || !line) {
- fprintf(stderr, "_glh_oldest_line: NULL argument(s).\n");
- return NULL;
- };
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->buffer || glh->max_lines == 0)
- return NULL;
-/*
- * Check the line dimensions.
- */
- if(dim < strlen(line) + 1) {
- fprintf(stderr,
- "_glh_oldest_line: 'dim' inconsistent with strlen(line) contents.\n");
- return NULL;
- };
-/*
- * Is this the start of a new search?
- */
- first = glh->recall==NULL;
-/*
- * If this is the first search backwards, save the current line
- * for potential recall later, and mark it as the last line
- * recalled.
- */
- if(first) {
- if(_glh_add_history(glh, line, 1))
- return NULL;
- glh->recall = glh->list.tail;
- };
-/*
- * Locate the oldest line that belongs to the current group.
- */
- for(node=glh->list.head; node && node->group != glh->group;
- node = node->next)
- ;
-/*
- * No line found?
- */
- if(!node)
- return NULL;
-/*
- * Record the above node as the starting point for subsequent
- * searches.
- */
- glh->recall = node;
-/*
- * Copy the recalled line into the provided line buffer.
- */
- strncpy(line, glh->buffer + node->start, dim);
- line[dim-1] = '\0';
- return line;
-}
-
-/*.......................................................................
- * Recall the line that was being entered when the search started.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * line char * The input line buffer. On input this should contain
- * the current input line, and on output, its contents
- * will have been replaced with the line that was
- * being entered when the search was started.
- * dim size_t The allocated dimensions of the line buffer.
- * Output:
- * return char * A pointer to line[0], or NULL if not found.
- */
-char *_glh_current_line(GlHistory *glh, char *line, size_t dim)
-{
-/*
- * Check the arguments.
- */
- if(!glh || !line) {
- fprintf(stderr, "_glh_current_line: NULL argument(s).\n");
- return NULL;
- };
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->buffer || glh->max_lines == 0)
- return NULL;
-/*
- * Check the line dimensions.
- */
- if(dim < strlen(line) + 1) {
- fprintf(stderr,
- "_glh_current_line: 'dim' inconsistent with strlen(line) contents.\n");
- return NULL;
- };
-/*
- * Restore the original line.
- */
- return _glh_restore_line(glh, line, dim);
-}
-
-/*.......................................................................
- * Remove the line that was originally being edited when the history
- * traversal was started, from its saved position in the history list,
- * and place it in the provided line buffer.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * line char * The input line buffer. On input this should contain
- * the current input line, and on output, its contents
- * will have been replaced with the saved line.
- * dim size_t The allocated dimensions of the line buffer.
- * Output:
- * return char * A pointer to line[0], or NULL if not found.
- */
-static char *_glh_restore_line(GlHistory *glh, char *line, size_t dim)
-{
- GlLineNode *tail; /* The tail node to be discarded */
-/*
- * If there wasn't a search in progress, do nothing.
- */
- if(!glh->recall)
- return NULL;
-/*
- * Get the list node that is to be removed.
- */
- tail = glh->list.tail;
-/*
- * If a pointer to the saved line is being used to record the
- * current search prefix, reestablish the search prefix, to
- * have it recorded by another history line if possible.
- */
- if(glh->prefix == glh->buffer + tail->start)
- (void) _glh_search_prefix(glh, glh->buffer + tail->start, glh->prefix_len);
-/*
- * Copy the recalled line into the input-line buffer.
- */
- strncpy(line, glh->buffer + tail->start, dim);
- line[dim-1] = '\0';
-/*
- * Discard the line-location node.
- */
- _glh_discard_node(glh, tail);
-/*
- * Mark the search as ended.
- */
- glh->recall = NULL;
- return line;
-}
-
-/*.......................................................................
- * Query the id of a history line offset by a given number of lines from
- * the one that is currently being recalled. If a recall session isn't
- * in progress, or the offset points outside the history list, 0 is
- * returned.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * offset int The line offset (0 for the current line, < 0
- * for an older line, > 0 for a newer line.
- * Output:
- * return GlhLineID The identifier of the line that is currently
- * being recalled, or 0 if no recall session is
- * currently in progress.
- */
-GlhLineID _glh_line_id(GlHistory *glh, int offset)
-{
- GlLineNode *node; /* The line location node being checked */
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->buffer || glh->max_lines == 0)
- return 0;
-/*
- * Search forward 'offset' lines to find the required line.
- */
- if(offset >= 0) {
- for(node=glh->recall; node && offset != 0; node=node->next) {
- if(node->group == glh->group)
- offset--;
- };
- } else {
- for(node=glh->recall; node && offset != 0; node=node->prev) {
- if(node->group == glh->group)
- offset++;
- };
- };
- return node ? node->id : 0;
-}
-
-/*.......................................................................
- * Recall a line by its history buffer ID. If the line is no longer
- * in the buffer, or the id is zero, NULL is returned.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * id GlhLineID The ID of the line to be returned.
- * line char * The input line buffer. On input this should contain
- * the current input line, and on output, its contents
- * will have been replaced with the saved line.
- * dim size_t The allocated dimensions of the line buffer.
- * Output:
- * return char * A pointer to line[0], or NULL if not found.
- */
-char *_glh_recall_line(GlHistory *glh, GlhLineID id, char *line, size_t dim)
-{
- GlLineNode *node; /* The line location node being checked */
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->buffer || glh->max_lines == 0)
- return NULL;
-/*
- * If we are starting a new recall session, save the current line
- * for potential recall later.
- */
- if(!glh->recall && _glh_add_history(glh, line, 1))
- return NULL;
-/*
- * Search for the specified line.
- */
- node = _glh_find_id(glh, id);
-/*
- * Not found?
- */
- if(!node || node->group != glh->group)
- return NULL;
-/*
- * Record the node of the matching line as the starting point
- * for subsequent searches.
- */
- glh->recall = node;
-/*
- * Copy the recalled line into the provided line buffer.
- */
- strncpy(line, glh->buffer + node->start, dim);
- line[dim-1] = '\0';
- return line;
-}
-
-/*.......................................................................
- * Save the current history in a specified file.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * filename const char * The name of the new file to record the
- * history in.
- * comment const char * Extra information such as timestamps will
- * be recorded on a line started with this
- * string, the idea being that the file can
- * double as a command file. Specify "" if
- * you don't care.
- * max_lines int The maximum number of lines to save, or -1
- * to save all of the lines in the history
- * list.
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-int _glh_save_history(GlHistory *glh, const char *filename, const char *comment,
- int max_lines)
-{
- FILE *fp; /* The output file */
- GlLineNode *node; /* The line being saved */
- GlLineNode *head; /* The head of the list of lines to be saved */
-/*
- * Check the arguments.
- */
- if(!glh || !filename || !comment) {
- fprintf(stderr, "_glh_save_history: NULL argument(s).\n");
- return 1;
- };
-/*
- * Attempt to open the specified file.
- */
- fp = fopen(filename, "w");
- if(!fp) {
- fprintf(stderr, "_glh_save_history: Can't open %s (%s).\n",
- filename, strerror(errno));
- return 1;
- };
-/*
- * If a ceiling on the number of lines to save was specified, count
- * that number of lines backwards, to find the first line to be saved.
- */
- head = NULL;
- if(max_lines >= 0) {
- for(head=glh->list.tail; head && --max_lines > 0; head=head->prev)
- ;
- };
- if(!head)
- head = glh->list.head;
-/*
- * Write the contents of the history buffer to the history file, writing
- * associated data such as timestamps, to a line starting with the
- * specified comment string.
- */
- for(node=head; node; node=node->next) {
-/*
- * Write peripheral information associated with the line, as a comment.
- */
- if(fprintf(fp, "%s ", comment) < 0 ||
- _glh_write_timestamp(fp, node->timestamp) ||
- fprintf(fp, " %u\n", node->group) < 0) {
- fprintf(stderr, "Error writing %s (%s).\n", filename, strerror(errno));
- (void) fclose(fp);
- return 1;
- };
-/*
- * Write the history line.
- */
- if(fprintf(fp, "%s\n", glh->buffer + node->start) < 0) {
- fprintf(stderr, "Error writing %s (%s).\n", filename, strerror(errno));
- (void) fclose(fp);
- return 1;
- };
- };
-/*
- * Close the history file.
- */
- if(fclose(fp) == EOF) {
- fprintf(stderr, "Error writing %s (%s).\n", filename, strerror(errno));
- return 1;
- };
- return 0;
-}
-
-/*.......................................................................
- * Restore previous history lines from a given file.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * filename const char * The name of the file to read from.
- * comment const char * The same comment string that was passed to
- * _glh_save_history() when this file was
- * written.
- * line char * A buffer into which lines can be read.
- * dim size_t The allocated dimension of line[].
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-int _glh_load_history(GlHistory *glh, const char *filename, const char *comment,
- char *line, size_t dim)
-{
- FILE *fp; /* The output file */
- size_t comment_len; /* The length of the comment string */
- time_t timestamp; /* The timestamp of the history line */
- unsigned group; /* The identifier of the history group to which */
- /* the line belongs. */
- int lineno; /* The line number being read */
-/*
- * Check the arguments.
- */
- if(!glh || !filename || !comment || !line) {
- fprintf(stderr, "_glh_load_history: NULL argument(s).\n");
- return 1;
- };
-/*
- * Measure the length of the comment string.
- */
- comment_len = strlen(comment);
-/*
- * Clear the history list.
- */
- _glh_clear_history(glh, 1);
-/*
- * Attempt to open the specified file. Don't treat it as an error
- * if the file doesn't exist.
- */
- fp = fopen(filename, "r");
- if(!fp)
- return 0;
-/*
- * Attempt to read each line and preceding peripheral info, and add these
- * to the history list.
- */
- for(lineno=1; fgets(line, dim, fp) != NULL; lineno++) {
- char *lptr; /* A pointer into the input line */
-/*
- * Check that the line starts with the comment string.
- */
- if(strncmp(line, comment, comment_len) != 0) {
- return _glh_cant_load_history(glh, filename, lineno,
- "Corrupt history parameter line", fp);
- };
-/*
- * Skip spaces and tabs after the comment.
- */
- for(lptr=line+comment_len; *lptr && (*lptr==' ' || *lptr=='\t'); lptr++)
- ;
-/*
- * The next word must be a timestamp.
- */
- if(_glh_decode_timestamp(lptr, &lptr, &timestamp)) {
- return _glh_cant_load_history(glh, filename, lineno,
- "Corrupt timestamp", fp);
- };
-/*
- * Skip spaces and tabs.
- */
- while(*lptr==' ' || *lptr=='\t')
- lptr++;
-/*
- * The next word must be an unsigned integer group number.
- */
- group = (int) strtoul(lptr, &lptr, 10);
- if(*lptr != ' ' && *lptr != '\n') {
- return _glh_cant_load_history(glh, filename, lineno,
- "Corrupt group id", fp);
- };
-/*
- * Skip spaces and tabs.
- */
- while(*lptr==' ' || *lptr=='\t')
- lptr++;
-/*
- * There shouldn't be anything left on the line.
- */
- if(*lptr != '\n') {
- return _glh_cant_load_history(glh, filename, lineno,
- "Corrupt parameter line", fp);
- };
-/*
- * Now read the history line itself.
- */
- lineno++;
- if(fgets(line, dim, fp) == NULL)
- return _glh_cant_load_history(glh, filename, lineno, "Read error", fp);
-/*
- * Append the line to the history buffer.
- */
- if(_glh_add_history(glh, line, 1)) {
- return _glh_cant_load_history(glh, filename, lineno,
- "Insufficient memory to record line", fp);
- };
-/*
- * Record the group and timestamp information along with the line.
- */
- if(glh->list.tail) {
- glh->list.tail->timestamp = timestamp;
- glh->list.tail->group = group;
- };
- };
-/*
- * Close the file.
- */
- (void) fclose(fp);
- return 0;
-}
-
-/*.......................................................................
- * This is a private error return function of _glh_load_history().
- */
-static int _glh_cant_load_history(GlHistory *glh, const char *filename,
- int lineno, const char *message, FILE *fp)
-{
- fprintf(stderr, "%s:%d: %s.\n", filename, lineno, message);
- (void) fclose(fp);
- return 1;
-}
-
-/*.......................................................................
- * Switch history groups.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * group unsigned The new group identifier. This will be recorded
- * with subsequent history lines, and subsequent
- * history searches will only return lines with
- * this group identifier. This allows multiple
- * separate history lists to exist within
- * a single GlHistory object. Note that the
- * default group identifier is 0.
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-int _glh_set_group(GlHistory *glh, unsigned group)
-{
-/*
- * Check the arguments.
- */
- if(!glh) {
- fprintf(stderr, "_glh_set_group: NULL argument(s).\n");
- return 1;
- };
-/*
- * Is the group being changed?
- */
- if(group != glh->group) {
-/*
- * Cancel any ongoing search.
- */
- if(_glh_cancel_search(glh))
- return 1;
-/*
- * Record the new group.
- */
- glh->group = group;
- };
- return 0;
-}
-
-/*.......................................................................
- * Query the current history group.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * Output:
- * return unsigned The group identifier.
- */
-int _glh_get_group(GlHistory *glh)
-{
- return glh ? glh->group : 0;
-}
-
-/*.......................................................................
- * Write a timestamp to a given stdio stream, in the format
- * yyyymmddhhmmss
- *
- * Input:
- * fp FILE * The stream to write to.
- * timestamp time_t The timestamp to be written.
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-static int _glh_write_timestamp(FILE *fp, time_t timestamp)
-{
- struct tm *t; /* THe broken-down calendar time */
-/*
- * Get the calendar components corresponding to the given timestamp.
- */
- if(timestamp < 0 || (t = localtime(&timestamp)) == NULL) {
- if(fprintf(fp, "?") < 0)
- return 1;
- return 0;
- };
-/*
- * Write the calendar time as yyyymmddhhmmss.
- */
- if(fprintf(fp, "%04d%02d%02d%02d%02d%02d", t->tm_year + 1900, t->tm_mon + 1,
- t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec) < 0)
- return 1;
- return 0;
-}
-
-/*.......................................................................
- * Read a timestamp from a string.
- *
- * Input:
- * string char * The string to read from.
- * Input/Output:
- * endp char ** On output *endp will point to the next unprocessed
- * character in string[].
- * timestamp time_t * The timestamp will be assigned to *t.
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-static int _glh_decode_timestamp(char *string, char **endp, time_t *timestamp)
-{
- unsigned year,month,day,hour,min,sec; /* Calendar time components */
- struct tm t;
-/*
- * There are 14 characters in the date format yyyymmddhhmmss.
- */
- enum {TSLEN=14};
- char timestr[TSLEN+1]; /* The timestamp part of the string */
-/*
- * If the time wasn't available at the time that the line was recorded
- * it will have been written as "?". Check for this before trying
- * to read the timestamp.
- */
- if(string[0] == '\?') {
- *endp = string+1;
- *timestamp = -1;
- return 0;
- };
-/*
- * The timestamp is expected to be written in the form yyyymmddhhmmss.
- */
- if(strlen(string) < TSLEN) {
- *endp = string;
- return 1;
- };
-/*
- * Copy the timestamp out of the string.
- */
- strncpy(timestr, string, TSLEN);
- timestr[TSLEN] = '\0';
-/*
- * Decode the timestamp.
- */
- if(sscanf(timestr, "%4u%2u%2u%2u%2u%2u", &year, &month, &day, &hour, &min,
- &sec) != 6) {
- *endp = string;
- return 1;
- };
-/*
- * Advance the string pointer over the successfully read timestamp.
- */
- *endp = string + TSLEN;
-/*
- * Copy the read values into a struct tm.
- */
- t.tm_sec = sec;
- t.tm_min = min;
- t.tm_hour = hour;
- t.tm_mday = day;
- t.tm_wday = 0;
- t.tm_yday = 0;
- t.tm_mon = month - 1;
- t.tm_year = year - 1900;
- t.tm_isdst = -1;
-/*
- * Convert the contents of the struct tm to a time_t.
- */
- *timestamp = mktime(&t);
- return 0;
-}
-
-/*.......................................................................
- * Display the contents of the history list.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * fp FILE * The stdio stream to write to.
- * fmt const char * A format string. This can contain arbitrary
- * characters, which are written verbatim, plus
- * any of the following format directives:
- * %D - The date, like 2001-11-20
- * %T - The time of day, like 23:59:59
- * %N - The sequential entry number of the
- * line in the history buffer.
- * %G - The history group number of the line.
- * %% - A literal % character.
- * %H - The history line.
- * all_groups int If true, display history lines from all
- * history groups. Otherwise only display
- * those of the current history group.
- * max_lines int If max_lines is < 0, all available lines
- * are displayed. Otherwise only the most
- * recent max_lines lines will be displayed.
- * Output:
- * return int 0 - OK.
- * 1 - Error.
- */
-int _glh_show_history(GlHistory *glh, FILE *fp, const char *fmt,
- int all_groups, int max_lines)
-{
- GlLineNode *node; /* The line being displayed */
- GlLineNode *oldest; /* The oldest line to display */
- enum {TSMAX=32}; /* The maximum length of the date and time string */
- char buffer[TSMAX+1]; /* The buffer in which to write the date and time */
- int idlen; /* The length of displayed ID strings */
- unsigned grpmax; /* The maximum group number in the buffer */
- int grplen; /* The number of characters needed to print grpmax */
-/*
- * Check the arguments.
- */
- if(!glh || !fp || !fmt) {
- fprintf(stderr, "_glh_show_history: NULL argument(s).\n");
- return 1;
- };
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->list.head)
- return 0;
-/*
- * Work out the length to display ID numbers, choosing the length of
- * the biggest number in the buffer. Smaller numbers will be padded
- * with leading zeroes if needed.
- */
- sprintf(buffer, "%lu", (unsigned long) glh->list.tail->id);
- idlen = strlen(buffer);
-/*
- * Find the largest group number.
- */
- grpmax = 0;
- for(node=glh->list.head; node; node=node->next) {
- if(node->group > grpmax)
- grpmax = node->group;
- };
-/*
- * Find out how many characters are needed to display the group number.
- */
- sprintf(buffer, "%u", (unsigned) grpmax);
- grplen = strlen(buffer);
-/*
- * Find the node that follows the oldest line to be displayed.
- */
- if(max_lines < 0) {
- oldest = glh->list.head;
- } else if(max_lines==0) {
- return 0;
- } else {
- for(oldest=glh->list.tail; oldest; oldest=oldest->prev) {
- if((all_groups || oldest->group == glh->group) && --max_lines <= 0)
- break;
- };
-/*
- * If the number of lines in the buffer doesn't exceed the specified
- * maximum, start from the oldest line in the buffer.
- */
- if(!oldest)
- oldest = glh->list.head;
- };
-/*
- * List the history lines in increasing time order.
- */
- for(node=oldest; node; node=node->next) {
-/*
- * Only display lines from the current history group, unless
- * told otherwise.
- */
- if(all_groups || node->group == glh->group) {
- const char *fptr; /* A pointer into the format string */
- struct tm *t = NULL; /* The broken time version of the timestamp */
-/*
- * Work out the calendar representation of the node timestamp.
- */
- if(node->timestamp != (time_t) -1)
- t = localtime(&node->timestamp);
-/*
- * Parse the format string.
- */
- fptr = fmt;
- while(*fptr) {
-/*
- * Search for the start of the next format directive or the end of the string.
- */
- const char *start = fptr;
- while(*fptr && *fptr != '%')
- fptr++;
-/*
- * Display any literal characters that precede the located directive.
- */
- if(fptr > start && fprintf(fp, "%.*s", (int) (fptr - start), start) < 0)
- return 1;
-/*
- * Did we hit a new directive before the end of the line?
- */
- if(*fptr) {
-/*
- * Obey the directive. Ignore unknown directives.
- */
- switch(*++fptr) {
- case 'D': /* Display the date */
- if(t && strftime(buffer, TSMAX, "%Y-%m-%d", t) != 0 &&
- fprintf(fp, "%s", buffer) < 0)
- return 1;
- break;
- case 'T': /* Display the time of day */
- if(t && strftime(buffer, TSMAX, "%H:%M:%S", t) != 0 &&
- fprintf(fp, "%s", buffer) < 0)
- return 1;
- break;
- case 'N': /* Display the sequential entry number */
- if(fprintf(fp, "%*lu", idlen, (unsigned long) node->id) < 0)
- return 1;
- break;
- case 'G':
- if(fprintf(fp, "%*u", grplen, (unsigned) node->group) < 0)
- return 1;
- break;
- case 'H': /* Display the history line */
- if(fprintf(fp, "%s", glh->buffer + node->start) < 0)
- return 1;
- break;
- case '%': /* A literal % symbol */
- if(fputc('%', fp) == EOF)
- return 1;
- break;
- };
-/*
- * Skip the directive.
- */
- if(*fptr)
- fptr++;
- };
- };
- };
- };
- return 0;
-}
-
-/*.......................................................................
- * Change the size of the history buffer.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * bufsize size_t The number of bytes in the history buffer, or 0
- * to delete the buffer completely.
- * Output:
- * return int 0 - OK.
- * 1 - Insufficient memory (the previous buffer
- * will have been retained). No error message
- * will be displayed.
- */
-int _glh_resize_history(GlHistory *glh, size_t bufsize)
-{
- GlLineNode *node; /* A line location node in the list of lines */
- GlLineNode *prev; /* The line location node preceding 'node' */
-/*
- * Check the arguments.
- */
- if(!glh)
- return bufsize > 0;
-/*
- * If the new size doesn't differ from the existing size, do nothing.
- */
- if(glh->buflen == bufsize)
- return 0;
-/*
- * Cancel any ongoing search.
- */
- (void) _glh_cancel_search(glh);
-/*
- * Create a wholly new buffer?
- */
- if(glh->buflen == 0) {
- glh->buffer = (char *) malloc(bufsize);
- if(!glh->buffer)
- return 1;
- glh->buflen = bufsize;
-/*
- * Delete an existing buffer?
- */
- } else if(bufsize == 0) {
- _glh_clear_history(glh, 1);
- free(glh->buffer);
- glh->buffer = NULL;
- glh->buflen = 0;
-/*
- * To get here, we must be shrinking or expanding from one
- * finite size to another.
- */
- } else {
-/*
- * If we are shrinking the size of the buffer, then we first need
- * to discard the oldest lines that won't fit in the new buffer.
- */
- if(bufsize < glh->buflen) {
- size_t nbytes = 0; /* The number of bytes used in the new buffer */
- GlLineNode *oldest; /* The oldest node to be kept */
-/*
- * Searching backwards from the youngest line, find the oldest
- * line for which there will be sufficient room in the new buffer.
- */
- for(oldest = glh->list.tail;
- oldest && (nbytes += oldest->nchar) <= bufsize;
- oldest = oldest->prev)
- ;
-/*
- * We will have gone one node too far, unless we reached the oldest line
- * without exceeding the target length.
- */
- if(oldest) {
- nbytes -= oldest->nchar;
- oldest = oldest->next;
- };
-/*
- * Discard the nodes that can't be retained.
- */
- while(glh->list.head && glh->list.head != oldest)
- _glh_discard_node(glh, glh->list.head);
-/*
- * If we are increasing the size of the buffer, we need to reallocate
- * the buffer before shifting the lines into their new positions.
- */
- } else {
- char *new_buffer = (char *) realloc(glh->buffer, bufsize);
- if(!new_buffer)
- return 1;
- glh->buffer = new_buffer;
- glh->buflen = bufsize;
- };
-/*
- * If there are any lines to be preserved, copy the block of lines
- * that precedes the end of the existing buffer to what will be
- * the end of the new buffer.
- */
- if(glh->list.head) {
- int shift; /* The number of bytes to shift lines in the buffer */
-/*
- * Get the oldest line to be kept.
- */
- GlLineNode *oldest = glh->list.head;
-/*
- * Count the number of characters that are used in the lines that
- * precede the end of the current buffer (ie. not including those
- * lines that have been wrapped to the start of the buffer).
- */
- int n = 0;
- for(node=oldest,prev=oldest->prev; node && node->start >= oldest->start;
- prev=node, node=node->next)
- n += node->nchar;
-/*
- * Move these bytes to the end of the resized buffer.
- */
- memmove(glh->buffer + bufsize - n, glh->buffer + oldest->start, n);
-/*
- * Adjust the buffer pointers to reflect the new locations of the moved
- * lines.
- */
- shift = bufsize - n - oldest->start;
- for(node=prev; node && node->start >= oldest->start; node=node->prev)
- node->start += shift;
- };
-/*
- * Shrink the buffer?
- */
- if(bufsize < glh->buflen) {
- char *new_buffer = (char *) realloc(glh->buffer, bufsize);
- if(new_buffer)
- glh->buffer = new_buffer;
- glh->buflen = bufsize; /* Mark it as shrunk, regardless of success */
- };
- };
- return 0;
-}
-
-/*.......................................................................
- * Set an upper limit to the number of lines that can be recorded in the
- * history list, or remove a previously specified limit.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * max_lines int The maximum number of lines to allow, or -1 to
- * cancel a previous limit and allow as many lines
- * as will fit in the current history buffer size.
- */
-void _glh_limit_history(GlHistory *glh, int max_lines)
-{
- if(!glh)
- return;
-/*
- * Apply a new limit?
- */
- if(max_lines >= 0 && max_lines != glh->max_lines) {
-/*
- * Count successively older lines until we reach the start of the
- * list, or until we have seen max_lines lines (at which point 'node'
- * will be line number max_lines+1).
- */
- int nline = 0;
- GlLineNode *node;
- for(node=glh->list.tail; node && ++nline <= max_lines; node=node->prev)
- ;
-/*
- * Discard any lines that exceed the limit.
- */
- if(node) {
- GlLineNode *oldest = node->next; /* The oldest line to be kept */
-/*
- * Delete nodes from the head of the list until we reach the node that
- * is to be kept.
- */
- while(glh->list.head && glh->list.head != oldest)
- _glh_discard_node(glh, glh->list.head);
- };
- };
-/*
- * Record the new limit.
- */
- glh->max_lines = max_lines;
- return;
-}
-
-/*.......................................................................
- * Discard either all history, or the history associated with the current
- * history group.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * all_groups int If true, clear all of the history. If false,
- * clear only the stored lines associated with the
- * currently selected history group.
- */
-void _glh_clear_history(GlHistory *glh, int all_groups)
-{
-/*
- * Check the arguments.
- */
- if(!glh)
- return;
-/*
- * Cancel any ongoing search.
- */
- (void) _glh_cancel_search(glh);
-/*
- * Delete all history lines regardless of group?
- */
- if(all_groups) {
- _rst_FreeList(glh->list.node_mem);
- glh->list.head = glh->list.tail = NULL;
- glh->nline = 0;
- glh->id_node = NULL;
-/*
- * Just delete lines of the current group?
- */
- } else {
- GlLineNode *node; /* The line node being checked */
- GlLineNode *prev; /* The line node that precedes 'node' */
- GlLineNode *next; /* The line node that follows 'node' */
-/*
- * Search out and delete the line nodes of the current group.
- */
- for(node=glh->list.head; node; node=next) {
-/*
- * Keep a record of the following node before we delete the current
- * node.
- */
- next = node->next;
-/*
- * Discard this node?
- */
- if(node->group == glh->group)
- _glh_discard_node(glh, node);
- };
-/*
- * If there are any lines left, and we deleted any lines, there will
- * be gaps in the buffer. These need to be removed.
- */
- if(glh->list.head) {
- int epos; /* The index of the last used element in the buffer */
-/*
- * Find the line nearest the end of the buffer.
- */
- GlLineNode *enode;
- for(node=glh->list.head, prev=NULL;
- node && node->start >= glh->list.head->start;
- prev=node, node = node->next)
- ;
- enode = prev;
-/*
- * Move the end line to abutt the end of the buffer, and remove gaps
- * between the lines that precede it.
- */
- epos = glh->buflen;
- for(node=enode; node; node=node->prev) {
- int shift = epos - (node->start + node->nchar);
- if(shift) {
- memmove(glh->buffer + node->start + shift,
- glh->buffer + node->start, node->nchar);
- node->start += shift;
- };
- epos = node->start;
- };
-/*
- * Move the first line in the buffer to the start of the buffer, and
- * remove gaps between the lines that follow it.
- */
- epos = 0;
- for(node=enode ? enode->next : NULL; node; node=node->next) {
- int shift = epos - node->start;
- if(shift) {
- memmove(glh->buffer + node->start + shift,
- glh->buffer + node->start, node->nchar);
- node->start += shift;
- };
- epos = node->start + node->nchar;
- };
- };
- };
- return;
-}
-
-/*.......................................................................
- * Temporarily enable or disable the history list.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * enable int If true, turn on the history mechanism. If
- * false, disable it.
- */
-void _glh_toggle_history(GlHistory *glh, int enable)
-{
- if(glh)
- glh->enable = enable;
-}
-
-/*.......................................................................
- * Remove a given line location node from the history list, and return
- * it to the freelist.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * node GlLineNode * The node to be removed. This must be currently
- * in the list who's head is glh->list.head, or
- * be NULL.
- */
-static void _glh_discard_node(GlHistory *glh, GlLineNode *node)
-{
- if(node) {
-/*
- * Make the node that precedes the node being removed point
- * to the one that follows it.
- */
- if(node->prev)
- node->prev->next = node->next;
- else
- glh->list.head = node->next;
-/*
- * Make the node that follows the node being removed point
- * to the one that precedes it.
- */
- if(node->next)
- node->next->prev = node->prev;
- else
- glh->list.tail = node->prev;
-/*
- * If we are deleting the node that is marked as the start point of the
- * last ID search, remove the cached starting point.
- */
- if(node == glh->id_node)
- glh->id_node = NULL;
-/*
- * Return the node to the free list.
- */
- node = (GlLineNode *) _del_FreeListNode(glh->list.node_mem, node);
-/*
- * Decrement the count of the number of lines in the buffer.
- */
- glh->nline--;
- };
-}
-
-/*.......................................................................
- * Lookup the details of a given history line, given its id.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * id GlLineID The sequential number of the line.
- * Input/Output:
- * line const char ** A pointer to the history line will be assigned
- * to *line.
- * group unsigned * The group membership of the line will be assigned
- * to *group.
- * timestamp time_t * The timestamp of the line will be assigned to
- * *timestamp.
- * Output:
- * return int 0 - The requested line wasn't found.
- * 1 - The line was found.
- */
-int _glh_lookup_history(GlHistory *glh, GlhLineID id, const char **line,
- unsigned *group, time_t *timestamp)
-{
- GlLineNode *node; /* The located line location node */
-/*
- * Check the arguments.
- */
- if(!glh)
- return 0;
-/*
- * Search for the line that has the specified ID.
- */
- node = _glh_find_id(glh, (GlhLineID) id);
-/*
- * Not found?
- */
- if(!node)
- return 0;
-/*
- * Return the details of the line.
- */
- if(line)
- *line = glh->buffer + node->start;
- if(group)
- *group = node->group;
- if(timestamp)
- *timestamp = node->timestamp;
- return 1;
-}
-
-/*.......................................................................
- * Lookup a node in the history list by its ID.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * id GlhLineID The ID of the line to be returned.
- * Output:
- * return GlLIneNode * The located node, or NULL if not found.
- */
-static GlLineNode *_glh_find_id(GlHistory *glh, GlhLineID id)
-{
- GlLineNode *node; /* The node being checked */
-/*
- * Is history enabled?
- */
- if(!glh->enable || !glh->list.head)
- return NULL;
-/*
- * If possible, start at the end point of the last ID search.
- * Otherwise start from the head of the list.
- */
- node = glh->id_node;
- if(!node)
- node = glh->list.head;
-/*
- * Search forwards from 'node'?
- */
- if(node->id < id) {
- while(node && node->id != id)
- node = node->next;
- glh->id_node = node ? node : glh->list.tail;
-/*
- * Search backwards from 'node'?
- */
- } else {
- while(node && node->id != id)
- node = node->prev;
- glh->id_node = node ? node : glh->list.head;
- };
-/*
- * Return the located node (this will be NULL if the ID wasn't found).
- */
- return node;
-}
-
-/*.......................................................................
- * Query the state of the history list. Note that any of the input/output
- * pointers can be specified as NULL.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * Input/Output:
- * enabled int * If history is enabled, *enabled will be
- * set to 1. Otherwise it will be assigned 0.
- * group unsigned * The current history group ID will be assigned
- * to *group.
- * max_lines int * The currently requested limit on the number
- * of history lines in the list, or -1 if
- * unlimited.
- */
-void _glh_state_of_history(GlHistory *glh, int *enabled, unsigned *group,
- int *max_lines)
-{
- if(glh) {
- if(enabled)
- *enabled = glh->enable;
- if(group)
- *group = glh->group;
- if(max_lines)
- *max_lines = glh->max_lines;
- };
-}
-
-/*.......................................................................
- * Get the range of lines in the history buffer.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * Input/Output:
- * oldest unsigned long * The sequential entry number of the oldest
- * line in the history list will be assigned
- * to *oldest, unless there are no lines, in
- * which case 0 will be assigned.
- * newest unsigned long * The sequential entry number of the newest
- * line in the history list will be assigned
- * to *newest, unless there are no lines, in
- * which case 0 will be assigned.
- * nlines int * The number of lines currently in the history
- * list.
- */
-void _glh_range_of_history(GlHistory *glh, unsigned long *oldest,
- unsigned long *newest, int *nlines)
-{
- if(glh) {
- if(oldest)
- *oldest = glh->list.head ? glh->list.head->id : 0;
- if(newest)
- *newest = glh->list.tail ? glh->list.tail->id : 0;
- if(nlines)
- *nlines = glh->nline;
- };
-}
-
-/*.......................................................................
- * Return the size of the history buffer and the amount of the
- * buffer that is currently in use.
- *
- * Input:
- * glh GlHistory * The input-line history maintenance object.
- * Input/Output:
- * buff_size size_t * The size of the history buffer (bytes).
- * buff_used size_t * The amount of the history buffer that
- * is currently occupied (bytes).
- */
-void _glh_size_of_history(GlHistory *glh, size_t *buff_size, size_t *buff_used)
-{
- if(glh) {
- if(buff_size)
- *buff_size = glh->buflen;
-/*
- * Determine the amount of buffer space that is currently occupied.
- */
- if(buff_used) {
- size_t used = 0;
- GlLineNode *node;
- for(node=glh->list.head; node; node=node->next)
- used += node->nchar;
- *buff_used = used;
- };
- };
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-04 18:53:04 +0000