alloc

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>

int IsBadData(char *pointer) {
  if (pointer == NULL) {
    perror("Bad alloc");
    free(pointer);
    return 1;
  }
  return 0;
}

int AddMemory(char *data, int *cap, int size) {
  if (*cap == size) {
    *cap *= 2;
    data = (char*)realloc(data, *cap);
    return IsBadData(data);
  }
  return 0;
}

int CmpStrings(const void *left, const void *right) {
  return strcmp(*(const char**)left, *(const char**)right);
}

int peekchar() {
  int c = getchar();
  if (c != EOF) {
    ungetc(c, stdin);  // puts it back
  }
  return c;
}

int free_data(char **data, int size) {
  for (int i = 0; i < size; ++i) {
    free(data[i]);
  }
  free(data);
  return 0;
}

int AddZero(char **data, int data_size, int size, int *cap) {
  if (data_size > 0) {
    if (AddMemory(data[data_size - 1], cap, size)) {
      free_data(data, data_size);
      return 1;
    }
    data[data_size - 1][size++] = '\0';
  }
  return 0;
}

int main() {
  size_t capasity = 1000;
  char** data = (char**)calloc(capasity, sizeof(char *));
  if (data == NULL) {
    perror("Bad alloc");
    free(data);
    return 1;
  }

  int data_size = 0;
  int size = 0; // size of current word
  int cap;  // capasity of memory, that alloc for current word
  int c;    // current char
  int prev_c = ' '; // previous char
  int quote = 0; // take the following values: 0, '\'', '\"'
  while ((c = getchar()) != EOF) {
    if (c == '\'' || c == '\"') {
      if (quote == 0) {
        quote = c;
        continue;
      }
      else if (quote == c) {
        quote = 0;
        continue;
      }
    }
    if (((c == '&' && peekchar() == '&') || (c == '|' && peekchar() == '|')) && quote == 0) {
      if (AddZero(data, data_size, size, &cap)) {
        return 1;
      }
      data[data_size++] = (char*)malloc(3 * sizeof(char));
      if (IsBadData(data[data_size - 1])) {
        free_data(data, data_size);
        return 1;
      }
      data[data_size - 1][0] = c;
      data[data_size - 1][1] = c;
      getchar();
      c = ' ';
    }
    else if ((c == ';' || c == '&' || c == '|') && quote == 0) {
      if (AddZero(data, data_size, size, &cap)) {
        return 1;
      }
      data[data_size++] = (char*)malloc(2 * sizeof(char));
      if (IsBadData(data[data_size - 1])) {
        free_data(data, data_size);
        return 1;
      }
      data[data_size - 1][0] = c;
      c = ' ';
    }
    else if (isspace(prev_c) && (!isspace(c) || quote != 0)) {
      if (AddZero(data, data_size, size, &cap)) {
        return 1;
      }
      data[data_size++] = (char*)malloc(sizeof(char));
      if (IsBadData(data[data_size - 1])) {
        free_data(data, data_size);
        return 1;
      }
      cap = 1;
      size = 0;
      data[data_size - 1][size++] = c;
    }
    else if (!isspace(prev_c) && (!isspace(c) || quote != 0)) {
      if (AddMemory(data[data_size - 1], &cap, size)) {
        free_data(data, data_size);
        return 1;
      }
      data[data_size - 1][size++] = c;
    }
    if (quote == 0) {
      prev_c = c;
    }
    else {
      prev_c = 'a';
    }
  }
  if (AddZero(data, data_size, size, &cap)) {
    return 1;
  }
  if (quote != 0) {
    perror("Incorrect input");
    free_data(data, data_size);
    return 1;
  }

  qsort(data, data_size, sizeof(char*), CmpStrings);
  for (int i = 0; i < data_size; ++i) {
    printf("\"%s\" \n", data[i]);
  }
  free_data(data, data_size);

  return 0;
}