Find all files/folders case-insensitively matching search criteria

main.c

// cc main.c -o main.out
// ./main.out <path>

#include <sys/types.h>
#include <sys/stat.h>
#include <ctype.h>
#include <dirent.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

static unsigned long long files_count = 0;
static const char *search_phrase = NULL;

typedef struct {
  char *name;
  node_list_t *children;
} node_t;

typedef struct {
  char *items;
} node_list_t;

static char *str_concat (const char *s1, const char *s2) {
  size_t l1 = strlen(s1);
  unsigned char has_trailing_slash = s1[l1 - 1] == '/';
  size_t l2 = strlen(s2);
  size_t len = l1 + (has_trailing_slash ? 0 : 1) + l2 + 1;
  char *result = malloc(len);

  if (result == NULL) {
    fprintf(stderr, "Failed to allocate %zu bytes.", len);
    return NULL;
  }

  sprintf(result, "%s%s%s", s1, has_trailing_slash ? "" : "/", s2);
  return result;
}

static int is_dir (const char *path) {
  struct stat buf;
  stat(path, &buf);
  return S_ISDIR(buf.st_mode);
}

static int traverse_dir (const char *path) {
  int status = 0;
  DIR *dir = opendir(path);

  if (dir == NULL) {
    fprintf(stderr, "Failed to open path '%s' for reading.\n", path);
    status = 1;
    goto FAIL_OPEN;
  }

  struct dirent *dp;

  while ((dp = readdir(dir)) != NULL) {
    if (strcmp(dp->d_name, ".") == 0 || strcmp(dp->d_name, "..") == 0) {
      continue;
    }

    char *entry_path = str_concat(path, dp->d_name);

    if (entry_path == NULL) {
      status = 1;
      goto FAIL_CONCAT;
    }

    if (strcasestr(dp->d_name, search_phrase) != NULL) {
      printf("found: %s\n", entry_path);
    }

    if (is_dir(entry_path)) {
      if (traverse_dir(entry_path) != 0) {
        status = 1;
        goto FAIL_TRAVERSE;
      }

      continue;
    }

    files_count += 1;
    free(entry_path);
  }

FAIL_CONCAT:
FAIL_TRAVERSE:
  closedir(dir);

FAIL_OPEN:
  return status;
}

int main (const int argc, const char **argv) {
  int status = 0;

  if (argc <= 1) {
    fprintf(stderr, "Path parameter is not set." "\n" "Usage: `./main.out <path> <search>`.\n");
    status = 1;
    goto FAIL_PARAMS;
  }

  if (argc <= 2) {
    fprintf(stderr, "Path parameter is not set." "\n" "Usage: `./main.out <path> <search>`.\n");
    status = 1;
    goto FAIL_PARAMS;
  }

  const char *relative_search_path = argv[1];
  search_phrase = argv[2];
  char *search_path = realpath(relative_search_path, NULL);

  if (search_path == NULL) {
    fprintf(stderr, "Failed to resolve real path.\n");
    status = 1;
    goto FAIL_PATH;
  }

  if (traverse_dir(search_path) != 0) {
    status = 1;
    goto FAIL_TRAVERSE;
  }

FAIL_TRAVERSE:
  free(search_path);

FAIL_PATH:
FAIL_PARAMS:
  if (files_count > 0) {
    printf("Files scanned: %llu\n", files_count);
  }

  return status == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
}