new getline tool with getline() & trim() function

c_pointers/getline.c

@@ -0,0 +1,78 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+
+char *getLine(void);
+char *trim(char *phrase);
+
+
+char *getLine(void) {
+
+    const size_t sizeIncrement = 10;
+    char *buffer = malloc(sizeIncrement);
+    char *currentPosition = buffer;
+    size_t maximumLength = sizeIncrement;
+    size_t length = 0;
+    int character;
+
+    if (currentPosition == NULL) {
+        return NULL;
+    }
+
+    while (1) {
+        character =fgetc(stdin);
+        if (character == '\n') {
+            break;
+        }
+        if (++length >= maximumLength) {
+            char *newBuffer = (char*) realloc(buffer, maximumLength += sizeIncrement);
+            if (newBuffer == NULL) {
+                free(buffer);
+                return NULL;
+            }
+            currentPosition = newBuffer + (currentPosition - buffer);
+            buffer = newBuffer;
+        }
+        *currentPosition++ = character;
+    }
+    *currentPosition = '\0';
+    return buffer;
+}
+
+
+char *trim(char *phrase) {
+
+    char *old = phrase;
+    char *new = phrase;
+
+    while (*old == ' ') {
+        old++;
+    }
+
+    while (*old) {
+        *new = *old;
+        new++;
+        old++;
+    }
+
+    *new = 0;
+    return (char*) realloc(phrase, strlen(phrase) + 1);
+}
+
+
+int main(void) {
+
+
+    char *buffer = trim(getLine());
+
+    if (buffer == NULL) {
+        printf("%s\n", "out of memory");
+    } else {
+        printf("%s\n", buffer);
+        free(buffer);
+    }
+
+    return 0;
+
+}