1 files changed, 218 insertions, 0 deletions
diff --git a/prism/util/pm_buffer.h b/prism/util/pm_buffer.h
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+++ b/prism/util/pm_buffer.h
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+/**
+ * @file pm_buffer.h
+ *
+ * A wrapper around a contiguous block of allocated memory.
+ */
+#ifndef PRISM_BUFFER_H
+#define PRISM_BUFFER_H
+
+#include "prism/defines.h"
+#include "prism/util/pm_char.h"
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+/**
+ * A pm_buffer_t is a simple memory buffer that stores data in a contiguous
+ * block of memory.
+ */
+typedef struct {
+    /** The length of the buffer in bytes. */
+    size_t length;
+
+    /** The capacity of the buffer in bytes that has been allocated. */
+    size_t capacity;
+
+    /** A pointer to the start of the buffer. */
+    char *value;
+} pm_buffer_t;
+
+/**
+ * Return the size of the pm_buffer_t struct.
+ *
+ * @returns The size of the pm_buffer_t struct.
+ */
+PRISM_EXPORTED_FUNCTION size_t pm_buffer_sizeof(void);
+
+/**
+ * Initialize a pm_buffer_t with the given capacity.
+ *
+ * @param buffer The buffer to initialize.
+ * @param capacity The capacity of the buffer.
+ * @returns True if the buffer was initialized successfully, false otherwise.
+ */
+bool pm_buffer_init_capacity(pm_buffer_t *buffer, size_t capacity);
+
+/**
+ * Initialize a pm_buffer_t with its default values.
+ *
+ * @param buffer The buffer to initialize.
+ * @returns True if the buffer was initialized successfully, false otherwise.
+ */
+PRISM_EXPORTED_FUNCTION bool pm_buffer_init(pm_buffer_t *buffer);
+
+/**
+ * Return the value of the buffer.
+ *
+ * @param buffer The buffer to get the value of.
+ * @returns The value of the buffer.
+ */
+PRISM_EXPORTED_FUNCTION char * pm_buffer_value(const pm_buffer_t *buffer);
+
+/**
+ * Return the length of the buffer.
+ *
+ * @param buffer The buffer to get the length of.
+ * @returns The length of the buffer.
+ */
+PRISM_EXPORTED_FUNCTION size_t pm_buffer_length(const pm_buffer_t *buffer);
+
+/**
+ * Append the given amount of space as zeroes to the buffer.
+ *
+ * @param buffer The buffer to append to.
+ * @param length The amount of space to append and zero.
+ */
+void pm_buffer_append_zeroes(pm_buffer_t *buffer, size_t length);
+
+/**
+ * Append a formatted string to the buffer.
+ *
+ * @param buffer The buffer to append to.
+ * @param format The format string to append.
+ * @param ... The arguments to the format string.
+ */
+void pm_buffer_append_format(pm_buffer_t *buffer, const char *format, ...) PRISM_ATTRIBUTE_FORMAT(2, 3);
+
+/**
+ * Append a string to the buffer.
+ *
+ * @param buffer The buffer to append to.
+ * @param value The string to append.
+ * @param length The length of the string to append.
+ */
+void pm_buffer_append_string(pm_buffer_t *buffer, const char *value, size_t length);
+
+/**
+ * Append a list of bytes to the buffer.
+ *
+ * @param buffer The buffer to append to.
+ * @param value The bytes to append.
+ * @param length The length of the bytes to append.
+ */
+void pm_buffer_append_bytes(pm_buffer_t *buffer, const uint8_t *value, size_t length);
+
+/**
+ * Append a single byte to the buffer.
+ *
+ * @param buffer The buffer to append to.
+ * @param value The byte to append.
+ */
+void pm_buffer_append_byte(pm_buffer_t *buffer, uint8_t value);
+
+/**
+ * Append a 32-bit unsigned integer to the buffer as a variable-length integer.
+ *
+ * @param buffer The buffer to append to.
+ * @param value The integer to append.
+ */
+void pm_buffer_append_varuint(pm_buffer_t *buffer, uint32_t value);
+
+/**
+ * Append a 32-bit signed integer to the buffer as a variable-length integer.
+ *
+ * @param buffer The buffer to append to.
+ * @param value The integer to append.
+ */
+void pm_buffer_append_varsint(pm_buffer_t *buffer, int32_t value);
+
+/**
+ * Append a double to the buffer.
+ *
+ * @param buffer The buffer to append to.
+ * @param value The double to append.
+ */
+void pm_buffer_append_double(pm_buffer_t *buffer, double value);
+
+/**
+ * The different types of escaping that can be performed by the buffer when
+ * appending a slice of Ruby source code.
+ */
+typedef enum {
+    PM_BUFFER_ESCAPING_RUBY,
+    PM_BUFFER_ESCAPING_JSON
+} pm_buffer_escaping_t;
+
+/**
+ * Append a slice of source code to the buffer.
+ *
+ * @param buffer The buffer to append to.
+ * @param source The source code to append.
+ * @param length The length of the source code to append.
+ * @param escaping The type of escaping to perform.
+ */
+void pm_buffer_append_source(pm_buffer_t *buffer, const uint8_t *source, size_t length, pm_buffer_escaping_t escaping);
+
+/**
+ * Prepend the given string to the buffer.
+ *
+ * @param buffer The buffer to prepend to.
+ * @param value The string to prepend.
+ * @param length The length of the string to prepend.
+ */
+void pm_buffer_prepend_string(pm_buffer_t *buffer, const char *value, size_t length);
+
+/**
+ * Concatenate one buffer onto another.
+ *
+ * @param destination The buffer to concatenate onto.
+ * @param source The buffer to concatenate.
+ */
+void pm_buffer_concat(pm_buffer_t *destination, const pm_buffer_t *source);
+
+/**
+ * Clear the buffer by reducing its size to 0. This does not free the allocated
+ * memory, but it does allow the buffer to be reused.
+ *
+ * @param buffer The buffer to clear.
+ */
+void pm_buffer_clear(pm_buffer_t *buffer);
+
+/**
+ * Strip the whitespace from the end of the buffer.
+ *
+ * @param buffer The buffer to strip.
+ */
+void pm_buffer_rstrip(pm_buffer_t *buffer);
+
+/**
+ * Checks if the buffer includes the given value.
+ *
+ * @param buffer The buffer to check.
+ * @param value The value to check for.
+ * @returns The index of the first occurrence of the value in the buffer, or
+ *   SIZE_MAX if the value is not found.
+ */
+size_t pm_buffer_index(const pm_buffer_t *buffer, char value);
+
+/**
+ * Insert the given string into the buffer at the given index.
+ *
+ * @param buffer The buffer to insert into.
+ * @param index The index to insert at.
+ * @param value The string to insert.
+ * @param length The length of the string to insert.
+ */
+void pm_buffer_insert(pm_buffer_t *buffer, size_t index, const char *value, size_t length);
+
+/**
+ * Free the memory associated with the buffer.
+ *
+ * @param buffer The buffer to free.
+ */
+PRISM_EXPORTED_FUNCTION void pm_buffer_free(pm_buffer_t *buffer);
+
+#endif