IO functions

include/io.h

@@ -0,0 +1,22 @@
+#ifndef IO_H
+#define IO_H
+
+#include "aliases.h"
+#include <linux/limits.h>
+#include <stdbool.h>
+#include <stdio.h>
+
+#define STREQ(S1, S2) (strcmp(S1, S2) == 0)
+
+typedef struct dirwalk dirwalk_t;
+typedef struct {
+  FILE *fp;
+  bool reading;
+  char name[NAME_MAX + 1];
+} dirwalk_result_t;
+
+u64 get_file_length(FILE *fp);
+void read_entire_file(void *dst, u64 length, FILE *fp);
+dirwalk_result_t walk_dir(dirwalk_t **dirwalk, const char *filepath);
+
+#endif // !IO_H

src/io.c

@@ -0,0 +1,179 @@
+#include "io.h"
+#include "aliases.h"
+#include "path_utils.h"
+#include <dirent.h>
+#include <linux/limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#define MAX_DIR_DEPTH PATH_MAX
+
+typedef struct stat stat_t;
+typedef struct dirent dirent_t;
+struct dirwalk {
+  u64 count;
+  FILE *current_file;
+  DIR *current_dir;
+  char dst[PATH_MAX];
+  DIR *directories[MAX_DIR_DEPTH];
+};
+
+u64 get_file_length(FILE *fp) {
+  u64 current = ftell(fp);
+
+  fseek(fp, 0, SEEK_END);
+
+  u64 length = ftell(fp);
+
+  // Restore the cursor position to where it was
+  fseek(fp, current, SEEK_SET);
+
+  return length;
+}
+
+void read_entire_file(void *dst, u64 length, FILE *fp) {
+  u64 current = ftell(fp);
+
+  fseek(fp, 0, SEEK_SET);
+
+  fread(dst, length, 1, fp);
+
+  fseek(fp, current, SEEK_SET);
+}
+
+dirwalk_result_t walk_dir(dirwalk_t **dirwalk, const char *filepath) {
+  if (!(*dirwalk)) {
+    *dirwalk = (dirwalk_t *)malloc(sizeof(dirwalk_t));
+    if (!(*dirwalk)) {
+      return (dirwalk_result_t){0};
+    }
+
+    memset((void *)(*dirwalk), 0, sizeof(dirwalk_t));
+
+    JOIN_PATH((*dirwalk)->dst, filepath);
+
+    (*dirwalk)->directories[0] = opendir((*dirwalk)->dst);
+    if (!((*dirwalk)->directories[0])) {
+      goto CLEANUP_WALK_DIR;
+    }
+
+    (*dirwalk)->current_dir = (*dirwalk)->directories[0];
+    ++((*dirwalk)->count);
+  }
+
+  if ((*dirwalk)->current_file) {
+    fclose((*dirwalk)->current_file);
+
+    (*dirwalk)->current_file = NULL;
+  }
+
+  dirwalk_t *dw = *dirwalk;
+
+  char tmp[PATH_MAX] = {0};
+
+  dirent_t *ep = NULL;
+  stat_t dirstat = {0};
+
+  while ((ep = readdir(dw->current_dir))) {
+    if (STREQ(ep->d_name, ".") || STREQ(ep->d_name, "..")) {
+      continue;
+    }
+
+    switch (ep->d_type) {
+    case DT_DIR: {
+      JOIN_PATH(dw->dst, ep->d_name);
+
+      dw->directories[(dw->count)++] = opendir(dw->dst);
+
+      dw->current_dir = dw->directories[dw->count - 1];
+
+      break;
+    }
+    case DT_REG: {
+      JOIN_PATH(tmp, dw->dst, ep->d_name);
+
+      dw->current_file = fopen(tmp, "rb");
+
+      dirwalk_result_t result = {0};
+
+      result.reading = true;
+      result.fp = dw->current_file;
+      strncpy(result.name, ep->d_name, NAME_MAX);
+
+      return result;
+    }
+    case DT_LNK: {
+      JOIN_PATH(tmp, dw->dst, ep->d_name);
+
+      u64 length = strlen(tmp);
+
+      stat(tmp, &dirstat);
+
+      if ((dirstat.st_mode & S_IFDIR) == S_IFDIR) {
+        memset(dw->dst, 0, length);
+
+        strncpy(dw->dst, tmp, length);
+
+        dw->directories[(dw->count)++] = opendir(dw->dst);
+
+        dw->current_dir = dw->directories[dw->count - 1];
+      } else if ((dirstat.st_mode & S_IFREG) == S_IFREG) {
+        dw->current_file = fopen(tmp, "rb");
+
+        dirwalk_result_t result = {0};
+
+        result.reading = true;
+        result.fp = dw->current_file;
+        strncpy(result.name, ep->d_name, NAME_MAX);
+
+        return result;
+      }
+
+      memset(tmp, 0, length);
+
+      break;
+    }
+    default:
+      break;
+    }
+  }
+
+  if (dw->count > 1) {
+    closedir(dw->directories[--(dw->count)]);
+    dw->directories[dw->count] = NULL;
+
+    dw->current_dir = dw->directories[dw->count - 1];
+
+    u64 length = strlen(dw->dst);
+
+    strncpy(tmp, dw->dst, length);
+
+    memset(dw->dst, 0, length);
+
+    DIRNAME(dw->dst, tmp);
+
+    memset(tmp, 0, length);
+
+    dirwalk_result_t result = {0};
+
+    result.reading = true;
+
+    return result;
+  } else {
+    dw->current_dir = NULL;
+  }
+
+  closedir(dw->directories[dw->count]);
+
+CLEANUP_WALK_DIR:
+  free(*dirwalk);
+  *dirwalk = NULL;
+
+  dirwalk_result_t result = {0};
+
+  result.reading = false;
+
+  return result;
+}