Rework string manipulation & minor improvements on webhook events

str.c

@@ -0,0 +1,244 @@
+/*
+ * Alertik: a tiny 'syslog' server & notification tool for Mikrotik routers.
+ * This is free and unencumbered software released into the public domain.
+ */
+
+/*
+ * String/append buffer implementation based on Aqua:
+ *  https://gist.github.com/Theldus/09ed2205aa5ba15cdf4571b71cd1c8fc
+ */
+
+#include "str.h"
+#include "log.h"
+
+/* Malloc is only used if AB_USE_MALLOC is defined. */
+#ifdef AB_USE_MALLOC
+#if defined(AB_CALLOC) && defined(AB_REALLOC) && defined(AB_FREE)
+#	define AB_USE_STDLIB
+#elif !defined(AB_CALLOC) && !defined(AB_REALLOC) && !defined(AB_FREE)
+#	define AB_USE_STDLIB
+#else
+#error "For custom memory allocators, you should define all three routines!"
+#error "Please define: AB_CALLOC, AB_REALLOC and AB_FREE!"
+#endif
+#endif
+
+#ifndef AB_CALLOC
+#define AB_CALLOC(nmemb,sz) calloc((nmemb),(sz))
+#define AB_REALLOC(p,newsz) realloc((p),(newsz))
+#define AB_FREE(p)          free((p))
+#endif
+
+#ifdef AB_USE_STDLIB
+#include <stdlib.h>
+#endif
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+
+/* ========================================================================= */
+/*                            BUFFER ROUTINES                                */
+/* ========================================================================= */
+
+#ifdef AB_USE_MALLOC
+/**
+ * @brief Rounds up to the next power of two.
+ *
+ * @param target Target number to be rounded.
+ *
+ * @return Returns the next power of two.
+ */
+static size_t next_power(size_t target)
+{
+	target--;
+	target |= target >> 1;
+	target |= target >> 2;
+	target |= target >> 4;
+	target |= target >> 8;
+	target |= target >> 16;
+	target++;
+	return (target);
+}
+#endif
+
+/**
+ * @brief Checks if the new size fits in the append buffer, if not,
+ * reallocates the buffer size by @p incr bytes.
+ *
+ * If the macro AB_USE_MALLOC is not defined (default), this only
+ * checks if the new size fits the buffer.
+ *
+ * @param sh Aqua highlight context.
+ * @param incr Size (in bytes) to be incremented.
+ *
+ * @return Returns 0 if success, -1 otherwise.
+ *
+ * @note The new size is the next power of two, that is capable
+ * to hold the required buffer size.
+ */
+static int increase_buff(struct str_ab *sh, size_t incr)
+{
+#ifndef AB_USE_MALLOC
+	if (sh->pos + incr >= MAX_LINE) {
+		log_msg("(increase buffer) Unable to fit appended message!\n");
+		log_msg("(static storage)  incr: %zu, buff_len: %zu, pos: %zu\n",
+			incr, sh->pos, sh->buff_len);
+		return (-1);
+	}
+#else
+	char *new;
+	size_t new_size;
+	if (sh->pos + incr >= sh->buff_len)
+	{
+		new_size = next_power(sh->buff_len + incr);
+		new = AB_REALLOC(sh->buff, new_size);
+		if (new == NULL)
+		{
+			AB_FREE(sh->buff);
+			sh->buff = NULL;
+
+			log_msg("(increase buffer) Unable to fit appended message!\n");
+			log_msg("(realloc storage) incr: %zu, buff_len: %zu, pos: %zu\n",
+				incr, sh->pos, sh->buff_len);
+			return (-1);
+		}
+		sh->buff_len = new_size;
+		sh->buff = new;
+	}
+#endif
+	return (0);
+}
+
+/**
+ * @brief Initializes the append buffer context.
+ *
+ * @param ab Append buffer structure.
+ *
+ * @return Returns 0 if success, -1 otherwise.
+ */
+int ab_init(struct str_ab *ab)
+{
+	if (!ab)
+		return (-1);
+
+	memset(ab, 0, sizeof(*ab));
+
+#ifndef AB_USE_MALLOC
+	ab->buff_len = MAX_LINE;
+#else
+	ab->buff = AB_CALLOC(MAX_LINE, 1);
+	if (!ab->buff)
+		return (-1);
+	ab->buff_len = MAX_LINE;
+#endif
+
+	return (0);
+}
+
+/**
+ * @brief Append a given char @p c into the buffer.
+ *
+ * @param sh Aqua highlight context.
+ * @param c Char to be appended.
+ *
+ * @return Returns 0 if success, -1 otherwise.
+ */
+int ab_append_chr(struct str_ab *sh, char c)
+{
+	if (increase_buff(sh, 2) < 0)
+		return (-1);
+
+	sh->buff[sh->pos + 0] = c;
+	sh->buff[sh->pos + 1] = '\0';
+	sh->pos++;
+	return (0);
+}
+
+/**
+ * @brief Appends a given string pointed by @p s of size @p len
+ * into the current buffer.
+ *
+ * If @p len is 0, the string is assumed to be null-terminated
+ * and its length is obtained.
+ *
+ * @param ab  Append buffer context.
+ * @param s   String to be append into the buffer.
+ * @param len String size, if 0, it's length is obtained.
+ *
+ * @return Returns 0 if success, -1 otherwise.
+ */
+int ab_append_str(struct str_ab *ab, const char *s, size_t len)
+{
+	if (!len)
+		len = strlen(s);
+
+	if (increase_buff(ab, len + 1) < 0)
+		return (-1);
+
+	memcpy(ab->buff + ab->pos, s, len);
+	ab->pos += len;
+	ab->buff[ab->pos] = '\0';
+	return (0);
+}
+
+/**
+ * @brief Appends a given formatted string pointed by @p fmt.
+ *
+ * @param ab  Append buffer context.
+ * @param fmt Formatted string to be appended.
+ *
+ * @return Returns 0 if success, -1 otherwise.
+ */
+int ab_append_fmt(struct str_ab *ab, const char *fmt, ...)
+{
+	int str_len, ab_len, orig_ab_pos;
+	char *buff_st;
+	va_list ap;
+
+	buff_st = ab->buff     + ab->pos;
+	ab_len  = ab->buff_len - ab->pos;
+
+	va_start(ap, fmt);
+		str_len = vsnprintf(buff_st, ab_len, fmt, ap);
+		if (str_len < 0) {
+			log_msg("Unable to fit appended message!\n");
+			return (-1);
+		}
+	va_end(ap);
+
+	/* If it fits, just happily returns. */
+	if (str_len + 1 <= ab_len) {
+		ab->pos += str_len;
+		return (0);
+	}
+
+	/* Otherwise, adjust current pos and try to increase buffer. */
+	else {
+		orig_ab_pos = ab->pos;
+
+		/* temporarily advance our buffer
+		 * to trick our increase buffer. */
+		ab->pos = ab->buff_len;
+
+		if (increase_buff(ab, (str_len + 1) - ab_len))
+			return (-1);
+
+		ab->pos = orig_ab_pos;
+	}
+
+	buff_st = ab->buff     + ab->pos;
+	ab_len  = ab->buff_len - ab->pos;
+
+	va_start(ap, fmt);
+		str_len = vsnprintf(buff_st, ab_len, fmt, ap);
+		if (str_len < 0 || (str_len + 1) > ab_len) {
+			log_msg("Unable to fit appended message!\n");
+			return (-1);
+		}
+	va_end(ap);
+
+	ab->pos += str_len;
+	return (0);
+}