diff options
| -rw-r--r-- | README.md | 1 | ||||
| -rw-r--r-- | src/df.c | 2 | ||||
| -rw-r--r-- | src/strings.c | 90 |
3 files changed, 92 insertions, 1 deletions
@@ -14,6 +14,7 @@ I try to follow the POSIX version of those commands for simplicity sake, e.g `ma | `echo` | display a line of text | | `yes` | output a string repeatedly until killed | | `df` | report free disk space | +| `strings` | find printable strings in files | ## Pending @@ -92,7 +92,7 @@ int main(int argc, char **argv) exit(1); } t_fs_info *last = &g_fs_infos[g_fs_infos_size - 1]; - fscanf(mounts_file, "%s %s", &last->name, &last->mount); + fscanf(mounts_file, "%s %s", last->name, last->mount); int c; do c = fgetc(mounts_file); diff --git a/src/strings.c b/src/strings.c new file mode 100644 index 0000000..a2349bd --- /dev/null +++ b/src/strings.c @@ -0,0 +1,90 @@ +#define _POSIX_C_SOURCE 200809L +#define _XOPEN_SOURCE 500 + +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <stdbool.h> +#include <ctype.h> + +static bool valid_char(int c) +{ + return isprint(c) || c == ' ' || c == '\t'; +} + +static size_t g_min_len = 4; +static char g_offset_format = -1; +static char *g_buf = NULL; + +static void strings(FILE *file) +{ + size_t buf_offset = 0; + int c; + while ((c = fgetc(file)) != EOF) + { + if (valid_char(c)) + { + if (buf_offset < g_min_len - 1) + { + g_buf[buf_offset] = c; + buf_offset++; + } + else + { + switch (g_offset_format) + { + case 'd': printf("%7ld ", ftell(file) - g_min_len); break; + case 'o': printf("%7lo ", ftell(file) - g_min_len); break; + case 'x': printf("%7lx ", ftell(file) - g_min_len); break; + } + fwrite(g_buf, sizeof(char), buf_offset, stdout); + buf_offset = 0; + fputc(c, stdout); + int c2; + while ((c2 = fgetc(file)) != EOF && valid_char(c2)) + fputc(c2, stdout); + fputc('\n', stdout); + } + } + else + buf_offset = 0; + } +} + +int main(int argc, char **argv) +{ + int option; + while ((option = getopt(argc, argv, "an:t:")) != -1) + { + switch (option) + { + case 'a': + break; + case 'n': + sscanf(optarg, "%lu", &g_min_len); + break; + case 't': + g_offset_format = optarg[0]; + break; + } + } + g_buf = malloc(sizeof(char) * g_min_len); + if (g_buf == NULL) + exit(1); + if (optind == argc) + { + strings(stdin); + free(g_buf); + return 0; + } + for (; optind < argc; optind++) + { + FILE *file = fopen(argv[optind], "r"); + if (file == NULL) + continue; + strings(file); + fclose(file); + } + free(g_buf); + return 0; +} |