diff options
| -rw-r--r-- | README.md | 8 | ||||
| -rw-r--r-- | src/df.c | 116 |
2 files changed, 122 insertions, 2 deletions
@@ -1,6 +1,7 @@ # coreutils Rewrite of some core utilities for educational purposes. +I try to follow the POSIX version of those commands for simplicity sake, e.g `man 1p ls`. | Name | Description | |------------|----------------------------------------------------------------- | @@ -12,20 +13,23 @@ Rewrite of some core utilities for educational purposes. | `shuf` | generate random permutations | | `echo` | display a line of text | | `yes` | output a string repeatedly until killed | +| `df` | report free disk space | + ## Pending -| Name | Description | +| Name | Description | |------------|----------------------------------------------------------------- | | `cut` | remove sections from each line of files | | `uniq` | report or omit repeated lines | | `tr` | translate or delete characters | | `chown` | change file owner and group | | `xargs` | construct argument lists and invoke utility | +| `ps` | report process status | ## TODO -| Name | Description | +| Name | Description | |------------|-----------------------------------------------------------------| | `cp` | | | `chmod` | | diff --git a/src/df.c b/src/df.c new file mode 100644 index 0000000..9c0b5eb --- /dev/null +++ b/src/df.c @@ -0,0 +1,116 @@ +#define _POSIX_C_SOURCE 200809L +#define _XOPEN_SOURCE 500 + +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <stdbool.h> +#include <string.h> +#include <sys/statvfs.h> +#include <math.h> +#include <limits.h> + +static unsigned long g_output_block_size = 512; + +typedef struct +{ + char name[PATH_MAX + 1]; + char mount[PATH_MAX + 1]; +} t_fs_info; + +static t_fs_info g_fs_info_dummy = { .name = "", .mount = "" }; + +static t_fs_info *g_fs_infos = NULL; +static size_t g_fs_infos_size = 0; + +void put_file_fs_info(char *file_relpath, bool allow_empty) +{ + char file_path[PATH_MAX + 1] = {'\0'}; + realpath(file_relpath, file_path); + + struct statvfs statvfsbuf; + if (statvfs(file_path, &statvfsbuf) == -1) + exit(1); + + long block_size = statvfsbuf.f_bsize; + unsigned long total = statvfsbuf.f_blocks * statvfsbuf.f_frsize / g_output_block_size; + long used = total - statvfsbuf.f_bfree * block_size / g_output_block_size; + long available = statvfsbuf.f_bavail * block_size / g_output_block_size; + + bool empty_fs = used + available == 0; + if (empty_fs && !allow_empty) + return; + + t_fs_info *fs_info = &g_fs_info_dummy; + for (size_t i = 0; i < g_fs_infos_size; i++) + { + char *mount = g_fs_infos[i].mount; + size_t mount_len = strlen(mount); + if (strncmp(file_path, mount, mount_len) == 0 && mount_len > strlen(fs_info->mount)) + fs_info = &g_fs_infos[i]; + } + + printf("%-15s", fs_info->name); + printf("%11ld", total); + printf("%9ld", used); + printf("%10ld", available); + if (!empty_fs) + printf("%8.0f%%", ceil(((double)used / (double)(used + available)) * 100)); + else + printf("%9c", '-'); + printf(" %s", fs_info->mount); + fputc('\n', stdout); +} + +int main(int argc, char **argv) +{ + int option; + + while ((option = getopt(argc, argv, "kPt")) != -1) + { + switch (option) + { + case 'k': + g_output_block_size = 1024; + break; + case 'P': + case 't': + break; + } + } + + FILE *mounts_file = fopen("/etc/mtab", "r"); + if (mounts_file == NULL) + exit(1); + while (!feof(mounts_file)) + { + g_fs_infos_size++; + g_fs_infos = realloc(g_fs_infos, sizeof(t_fs_info) * g_fs_infos_size); + if (g_fs_infos == NULL) + { + fclose(mounts_file); + exit(1); + } + t_fs_info *last = &g_fs_infos[g_fs_infos_size - 1]; + fscanf(mounts_file, "%s %s", &last->name, &last->mount); + int c; + do + c = fgetc(mounts_file); + while (c != '\n' && c != EOF); + } + fclose(mounts_file); + g_fs_infos_size--; + + printf("Filesystem %4lu-blocks Used Available Capacity Mounted on\n", g_output_block_size); + + if (optind == argc) + { + for (size_t i = 0; i < g_fs_infos_size; i++) + put_file_fs_info(g_fs_infos[i].mount, false); + return 0; + } + for (; optind < argc; optind++) + put_file_fs_info(argv[optind], true); + free(g_fs_infos); + return 0; +} |