seems like working lab2

2025-10-15 16:58:23 +07:00
parent 6036a989cf
commit e0d0c21c53
3 changed files with 216 additions and 0 deletions
--- a/lab_2/textlib.c
+++ b/lab_2/textlib.c
@@ -0,0 +1,93 @@
+#include <unistd.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+
+#define RBUFSZ 4096
+#define WBUFSZ 4096
+
+// Функция обработки текста
+long long process_text(const char *in_path, const char *out_path, long long cap) {
+    int in_fd = open(in_path, O_RDONLY);
+    if (in_fd < 0) {
+        return -1;
+    }
+
+    mode_t filePerms = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
+    int out_fd = open(out_path, O_CREAT | O_WRONLY | O_TRUNC, filePerms);
+    if (out_fd < 0) {
+        close(in_fd);
+        return -1;
+    }
+
+    char rbuf[RBUFSZ];
+    char wbuf[WBUFSZ];
+    size_t wlen = 0;
+
+    long long total_replacements = 0;
+    int at_line_start = 1;
+    unsigned char line_key = 0;
+    int replacing_enabled = 1;
+
+    for (;;) {
+        ssize_t n = read(in_fd, rbuf, sizeof(rbuf));
+        if (n > 0) {
+            for (ssize_t i = 0; i < n; i++) {
+                unsigned char c = (unsigned char) rbuf[i];
+
+                if (at_line_start) {
+                    line_key = c;
+                    at_line_start = 0;
+                }
+
+                unsigned char outc = c;
+                if (c == '\n') {
+                    at_line_start = 1;
+                } else if (replacing_enabled && c == line_key) {
+                    if (total_replacements < cap) {
+                        outc = ' ';
+                        total_replacements++;
+                        if (total_replacements == cap) {
+                            replacing_enabled = 0;
+                        }
+                    } else {
+                        replacing_enabled = 0;
+                    }
+                }
+
+                if (wlen == sizeof(wbuf)) {
+                    ssize_t wrote = write(out_fd, wbuf, wlen);
+                    if (wrote < 0 || (size_t) wrote != wlen) {
+                        close(in_fd);
+                        close(out_fd);
+                        return -1;
+                    }
+                    wlen = 0;
+                }
+                wbuf[wlen++] = (char) outc;
+            }
+        } else if (n == 0) {
+            if (wlen > 0) {
+                ssize_t wrote = write(out_fd, wbuf, wlen);
+                if (wrote < 0 || (size_t) wrote != wlen) {
+                    close(in_fd);
+                    close(out_fd);
+                    return -1;
+                }
+                wlen = 0;
+            }
+            break;
+        } else {
+            close(in_fd);
+            close(out_fd);
+            return -1;
+        }
+    }
+
+    close(in_fd);
+    close(out_fd);
+
+    return total_replacements;
+}