vlad-refactor

vlad/lab_2/Makefile

@@ -0,0 +1,52 @@
+# Makefile
+
+CC = gcc
+CFLAGS = -Wall -Wextra -O2
+PICFLAGS = -fPIC
+
+.PHONY: all dynamic static test-dynamic test-static clean
+
+all: dynamic static
+
+# --- Dynamic (shared) build ---
+dynamic: libtext.so main_d
+
+libtext.so: lib_d.o
+	$(CC) -shared -o $@ $^
+
+main_d: main_d.o
+	$(CC) -o $@ $^ -ldl
+
+lib_d.o: lib_d.c
+	$(CC) $(CFLAGS) $(PICFLAGS) -c $< -o $@
+
+# --- Static build ---
+static: libtext.a main_s
+
+libtext.a: lib_s.o
+	ar rcs $@ $^
+
+main_s: main_s.o libtext.a
+	$(CC) -o $@ main_s.o libtext.a
+
+# Generic rule for other .o files
+%.o: %.c
+	$(CC) $(CFLAGS) -c $< -o $@
+
+# --- Test targets ---
+# Creates a small `test_input.txt`, runs the program, and shows `out.txt`
+test-dynamic: dynamic
+	printf "Hello123456789\n!!@@2211122\n" > test_input.txt
+	./main_d test_input.txt out.txt 100 ./libtext.so
+	@echo "---- out.txt ----"
+	cat out.txt
+
+test-static: static
+	printf "Hello123456789\n!!@@2211122\n" > test_input.txt
+	./main_s test_input.txt out.txt 100
+	@echo "---- out.txt ----"
+	cat out.txt
+
+# --- Cleanup ---
+clean:
+	rm -f *.o *.so *.a main_d main_s test_input.txt out.txt

vlad/lab_2/lib_d.c

@@ -0,0 +1,35 @@
+#include <stddef.h>
+
+int replace_char(char *buf, int key, int *replacements_left) {
+    (void)key;
+    int replaced = 0;
+    size_t i = 0;
+
+    while (buf[i] != '\0') {
+        if (buf[i] == '\n') {
+            i++;
+            continue;
+        }
+
+        // Detect start of a symbol run
+        char symbol = buf[i];
+        size_t run_start = i;
+        size_t run_len = 1;
+
+        // Count length of run
+        while (buf[i + run_len] == symbol && buf[i + run_len] != '\n' && buf[i + run_len] != '\0') {
+            run_len++;
+        }
+
+        // For pairs and longer runs: replace every 2nd, 4th, ...
+        for (size_t j = 1; j < run_len && *replacements_left > 0; j += 2) {
+            buf[run_start + j] = ' ';
+            replaced++;
+            (*replacements_left)--;
+            if (*replacements_left == 0) break;
+        }
+
+        i += run_len;
+    }
+    return replaced;
+}

vlad/lab_2/lib_s.c

@@ -0,0 +1,35 @@
+#include <stddef.h>
+
+int replace_char(char *buf, int key, int *replacements_left) {
+    (void)key;
+    int replaced = 0;
+    size_t i = 0;
+
+    while (buf[i] != '\0') {
+        if (buf[i] == '\n') {
+            i++;
+            continue;
+        }
+
+        // Detect start of a symbol run
+        char symbol = buf[i];
+        size_t run_start = i;
+        size_t run_len = 1;
+
+        // Count length of run
+        while (buf[i + run_len] == symbol && buf[i + run_len] != '\n' && buf[i + run_len] != '\0') {
+            run_len++;
+        }
+
+        // For pairs and longer runs: replace every 2nd, 4th, ...
+        for (size_t j = 1; j < run_len && *replacements_left > 0; j += 2) {
+            buf[run_start + j] = ' ';
+            replaced++;
+            (*replacements_left)--;
+            if (*replacements_left == 0) break;
+        }
+
+        i += run_len;
+    }
+    return replaced;
+}

vlad/lab_2/main_d.c

@@ -0,0 +1,62 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <dlfcn.h>
+
+#define MAX_LINE 4096
+
+typedef int (*replace_func_t)(char*, int, int*);
+
+int main(int argc, char *argv[]) {
+    if (argc != 5) {
+        fprintf(stderr, "Usage: %s <in> <out> <cap> <path_to_so>\n", argv[0]);
+        return 1;
+    }
+
+    FILE *fin = fopen(argv[1], "r");
+    if (!fin) { perror("fopen input"); return 1; }
+    FILE *fout = fopen(argv[2], "w");
+    if (!fout) { perror("fopen output"); fclose(fin); return 1; }
+
+    int cap = atoi(argv[3]);
+    if (cap < 0) {
+        fprintf(stderr, "invalid cap\n");
+        fclose(fin);
+        fclose(fout);
+        return 1;
+    }
+
+    void *lib = dlopen(argv[4], RTLD_LAZY);
+    if (!lib) {
+        fprintf(stderr, "dlopen error: %s\n", dlerror());
+        fclose(fin);
+        fclose(fout);
+        return 1;
+    }
+
+    replace_func_t replace = (replace_func_t)dlsym(lib, "replace_char");
+    if (!replace) {
+        fprintf(stderr, "dlsym error: %s\n", dlerror());
+        dlclose(lib);
+        fclose(fin);
+        fclose(fout);
+        return 1;
+    }
+
+    int total = 0;
+    char line[MAX_LINE];
+
+    while (fgets(line, sizeof(line), fin)) {
+        if (cap > 0) {
+            int key = (unsigned char)line[0];
+            int repl_line = replace(line, key, &cap);
+            total += repl_line;
+        }
+        fputs(line, fout);
+    }
+
+    dlclose(lib);
+    fclose(fin);
+    fclose(fout);
+    printf("total_replacements: %d\n", total);
+    return 0;
+}

vlad/lab_2/main_s.c

@@ -0,0 +1,44 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#define MAX_LINE 4096
+
+int replace_char(char *buf, int key, int *replacements_left);
+
+int main(int argc, char *argv[]) {
+    if (argc != 4) {
+        fprintf(stderr, "Usage: %s <in> <out> <cap>\n", argv[0]);
+        return 1;
+    }
+
+    FILE *fin = fopen(argv[1], "r");
+    if (!fin) { perror("fopen input"); return 1; }
+    FILE *fout = fopen(argv[2], "w");
+    if (!fout) { perror("fopen output"); fclose(fin); return 1; }
+
+    int cap = atoi(argv[3]);
+    if (cap < 0) {
+        fprintf(stderr, "invalid cap\n");
+        fclose(fin);
+        fclose(fout);
+        return 1;
+    }
+
+    int total = 0;
+    char line[MAX_LINE];
+
+    while (fgets(line, sizeof(line), fin)) {
+        if (cap > 0) {
+            // key is unused, but pass the first byte for symmetry
+            int key = (unsigned char)line[0];
+            int repl_line = replace_char(line, key, &cap);
+            total += repl_line;
+        }
+        fputs(line, fout);
+    }
+
+    fclose(fin);
+    fclose(fout);
+    printf("total_replacements: %d\n", total);
+    return 0;
+}