1 files changed, 130 insertions, 0 deletions
diff --git a/advent-of-code/2022/lib/str.c b/advent-of-code/2022/lib/str.c
new file mode 100644
index 0000000..16968a2
--- /dev/null
+++ b/advent-of-code/2022/lib/str.c
@@ -0,0 +1,130 @@
+#include "str.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include <ctype.h>
+
+char** str_split(char *str, char delim) {
+    char **ret;
+
+    if (str == NULL) return NULL;
+    if (*str == '\n') {
+        ret = malloc(sizeof(char*));
+        *ret = NULL;
+        return ret;
+    }
+    int count = 0;
+    char *begin = str;
+    for (char *p = str; *p != '\0'; p++) {
+        if (*p != delim && !(delim == '\0' && isspace(*p))) {
+            continue;
+        }
+        int size = p - begin;
+        if (size > 0) count++;
+    }
+    count++;
+    ret = malloc((count + 1) * sizeof(char*));
+    memset(ret, 0, (count + 1) * sizeof(char*));
+
+    begin = str;
+    int i = 0;
+    bool finished = false;
+    for (char *p = str; !finished; p++) {
+        if (*p == '\0') finished = true;
+        if (*p != delim && *p != '\0' && !(delim == '\0' && isspace(*p))) {
+            continue;
+        }
+        int size = p - begin;
+        if (size == 0) {
+            begin = p + 1;
+            continue;
+        }
+        char *buf = malloc(sizeof(char) * (size + 1));
+        buf[size] = '\0';
+        memcpy(buf, begin, size * sizeof(char));
+        begin = p + 1;
+        ret[i] = buf;
+        i++;
+    }
+    return ret;
+}
+
+void str_list_free(char **list) {
+    char **p = list;
+    while (*p != NULL) {
+        free(*p);
+        p++;
+    }
+    free(list);
+}
+
+char* str_strip(char *str) {
+    int len = strlen(str);
+    char *begin = str;
+    char *end = str + len - 1;
+    while (isspace(*begin) && begin < end) {
+        begin++;
+    }
+    while (isspace(*end) && end >= begin) {
+        end--;
+    }
+    len = end - begin + 1;
+    char *buf = malloc(sizeof(char) * (len) + 1);
+    buf[len] = '\0';
+    memcpy(buf, begin, len);
+    return buf;
+}
+
+void sb_init(StrBuilder *sb) {
+    *sb = (StrBuilder){.size = 0, .cap = 16};
+    sb->buf = malloc(sizeof(char) * 17);
+}
+
+static void sb_reserve(StrBuilder *sb, int extra) {
+    if (sb->size + extra <= sb->cap) {
+        return;
+    }
+    int new_cap = (sb->size + extra) * 2;
+    sb->buf = realloc(sb->buf, new_cap + 1);
+    memset(sb->buf + sb->cap, 0, new_cap - sb->cap + 1);
+    sb->cap = new_cap;
+}
+
+void sb_append(StrBuilder *sb, char *format, ...) {
+    va_list va1;
+    va_list va2;
+    va_start(va1, format);
+    va_copy(va2, va1);
+    int size = vsnprintf(NULL, 0, format, va1);
+    sb_reserve(sb, size);
+    vsnprintf(sb->buf + sb->size, sb->cap - sb->size + 1, format, va2);
+}
+
+void sb_appendc(StrBuilder *sb, char c) {
+    sb_reserve(sb, 1);
+    sb->buf[sb->size] = c;
+    sb->size++;
+}
+
+char* fgetline(FILE *fp) {
+    StrBuilder sb;
+    sb_init(&sb);
+    while (true) {
+        int c = fgetc(fp);
+        if (c == EOF && sb.size == 0) return NULL;
+        if (c != EOF) sb_appendc(&sb, c);
+        if (c == EOF || c == '\n') return sb.buf;
+    }
+    return NULL;
+}
+
+int fpeek(FILE *fp) {
+    int c = fgetc(fp);
+    if (c == EOF) return c;
+    ungetc(c, fp);
+    return c;
+}