From fc22ddcd671e4d885bac8a0c22ea62f3ea585c9d Mon Sep 17 00:00:00 2001
From: Aleksey Lobanov <i@likemath.ru>
Date: Sat, 31 Oct 2020 15:06:57 +0300
Subject: [PATCH] hw5: Demo sources added

---
 05_Environmental/pcredemo.c | 72 +++++++++++++++++++++++++++++++++++++
 05_Environmental/window.c   | 38 ++++++++++++++++++++
 2 files changed, 110 insertions(+)
 create mode 100644 05_Environmental/pcredemo.c
 create mode 100644 05_Environmental/window.c

diff --git a/05_Environmental/pcredemo.c b/05_Environmental/pcredemo.c
new file mode 100644
index 0000000..c83bf74
--- /dev/null
+++ b/05_Environmental/pcredemo.c
@@ -0,0 +1,72 @@
+#ifndef PCRE2_CODE_UNIT_WIDTH
+#define PCRE2_CODE_UNIT_WIDTH 8
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <pcre2.h>
+
+int main(int argc, char **argv)
+{
+    pcre2_code *re;
+    PCRE2_SPTR pattern;     /* PCRE2_SPTR is a pointer to unsigned code units of */
+    PCRE2_SPTR subject;     /* the appropriate width (in this case, 8 bits). */
+
+    int errnum;
+    int i, rc;
+
+    PCRE2_SIZE erroffs;
+    PCRE2_SIZE *ovector;
+    PCRE2_SIZE subject_length;
+
+    pcre2_match_data *match_data;
+
+    if (argc != 3) {
+        printf("Exactly two arguments required: a regex and a subject string\n");
+        return 1;
+    }
+
+    pattern = (PCRE2_SPTR)argv[1];
+    subject = (PCRE2_SPTR)argv[2];
+    subject_length = (PCRE2_SIZE)strlen((char *)subject);
+
+    re = pcre2_compile(pattern, PCRE2_ZERO_TERMINATED, PCRE2_UCP, &errnum, &erroffs, NULL);
+
+    if (re == NULL) {
+        PCRE2_UCHAR buffer[256];
+        pcre2_get_error_message(errnum, buffer, sizeof(buffer));
+        printf("PCRE2 compilation failed at offset %d: %s\n", (int)erroffs,
+               buffer);
+        return 1;
+    }
+
+    match_data = pcre2_match_data_create_from_pattern(re, NULL);
+
+    rc = pcre2_match(re, subject, subject_length, 0, 0, match_data, NULL);
+
+    if (rc < 0) {
+        switch(rc) {
+        case PCRE2_ERROR_NOMATCH:
+            printf("No match\n");
+            break;
+        default:
+            printf("Matching error %d\n", rc);
+            break;
+        }
+        pcre2_match_data_free(match_data);   /* Release memory used for the match */
+        pcre2_code_free(re);                 /*   data and the compiled pattern. */
+        return 1;
+    }
+
+    ovector = pcre2_get_ovector_pointer(match_data);
+
+    for (i = 0; i < rc; i++)
+        printf("%2ld: %.*s\n", ovector[2*i], 
+			     (int)(ovector[2*i+1] - ovector[2*i]),
+			     subject + ovector[2*i]);
+
+    pcre2_match_data_free(match_data);  /* Release the memory that was used */
+    pcre2_code_free(re);                /* for the match data and the pattern. */
+
+    return 0;
+}
diff --git a/05_Environmental/window.c b/05_Environmental/window.c
new file mode 100644
index 0000000..398e46b
--- /dev/null
+++ b/05_Environmental/window.c
@@ -0,0 +1,38 @@
+#include <ncurses.h>
+
+#define DX 3
+#define ONLELINE 3
+#define MAXSTR 80
+
+void main() {
+	WINDOW *winA, *winB, *winO;
+	char inA[MAXSTR], inB[MAXSTR];
+	int c = 0;
+	int half;
+
+	initscr();
+	cbreak();
+	printw("Input:");
+	refresh();
+
+	half = (COLS-2*DX)/2;
+	winA = newwin(ONLELINE, half, DX, DX);
+	winB = newwin(ONLELINE, half, DX, DX+half);
+	winO = newwin(LINES-ONLELINE-DX*2, (COLS-2*DX), DX+ONLELINE, DX);
+	keypad(winA, TRUE);
+	keypad(winB, TRUE);
+	scrollok (winO, TRUE);
+	wmove(winO, 1, 0);
+	do {
+		werase(winA); box(winA, 0, 0);
+		mvwgetnstr(winA, 1, 1, inA, MAXSTR);
+		werase(winB); box(winB, 0, 0);
+		mvwgetnstr(winB, 1, 1, inB, MAXSTR);
+		wprintw(winO, "  Entered: %s %s\n", inA, inB);
+		box(winO, 0, 0);
+		wrefresh(winO);
+	} while(*inA);
+
+	endwin();
+
+}