1 files changed, 62 insertions, 0 deletions

diff --git a/argv-array.h b/argv-array.h
index a39ba43f57..a7d3b10707 100644
--- a/argv-array.h
+++ b/argv-array.h
@@ -1,8 +1,32 @@
 #ifndef ARGV_ARRAY_H
 #define ARGV_ARRAY_H
 
+/**
+ * The argv-array API allows one to dynamically build and store
+ * NULL-terminated lists.  An argv-array maintains the invariant that the
+ * `argv` member always points to a non-NULL array, and that the array is
+ * always NULL-terminated at the element pointed to by `argv[argc]`. This
+ * makes the result suitable for passing to functions expecting to receive
+ * argv from main().
+ *
+ * The string-list API (documented in string-list.h) is similar, but cannot be
+ * used for these purposes; instead of storing a straight string pointer,
+ * it contains an item structure with a `util` field that is not compatible
+ * with the traditional argv interface.
+ *
+ * Each `argv_array` manages its own memory. Any strings pushed into the
+ * array are duplicated, and all memory is freed by argv_array_clear().
+ */
+
 extern const char *empty_argv[];
 
+/**
+ * A single array. This should be initialized by assignment from
+ * `ARGV_ARRAY_INIT`, or by calling `argv_array_init`. The `argv`
+ * member contains the actual array; the `argc` member contains the
+ * number of elements in the array, not including the terminating
+ * NULL.
+ */
 struct argv_array {
 	const char **argv;
 	int argc;
@@ -11,17 +35,55 @@ struct argv_array {
 
 #define ARGV_ARRAY_INIT { empty_argv, 0, 0 }
 
+/**
+ * Initialize an array. This is no different than assigning from
+ * `ARGV_ARRAY_INIT`.
+ */
 void argv_array_init(struct argv_array *);
+
+/* Push a copy of a string onto the end of the array. */
 const char *argv_array_push(struct argv_array *, const char *);
+
+/**
+ * Format a string and push it onto the end of the array. This is a
+ * convenience wrapper combining `strbuf_addf` and `argv_array_push`.
+ */
 __attribute__((format (printf,2,3)))
 const char *argv_array_pushf(struct argv_array *, const char *fmt, ...);
+
+/**
+ * Push a list of strings onto the end of the array. The arguments
+ * should be a list of `const char *` strings, terminated by a NULL
+ * argument.
+ */
 LAST_ARG_MUST_BE_NULL
 void argv_array_pushl(struct argv_array *, ...);
+
+/* Push a null-terminated array of strings onto the end of the array. */
 void argv_array_pushv(struct argv_array *, const char **);
+
+/**
+ * Remove the final element from the array. If there are no
+ * elements in the array, do nothing.
+ */
 void argv_array_pop(struct argv_array *);
+
 /* Splits by whitespace; does not handle quoted arguments! */
 void argv_array_split(struct argv_array *, const char *);
+
+/**
+ * Free all memory associated with the array and return it to the
+ * initial, empty state.
+ */
 void argv_array_clear(struct argv_array *);
+
+/**
+ * Disconnect the `argv` member from the `argv_array` struct and
+ * return it. The caller is responsible for freeing the memory used
+ * by the array, and by the strings it references. After detaching,
+ * the `argv_array` is in a reinitialized state and can be pushed
+ * into again.
+ */
 const char **argv_array_detach(struct argv_array *);
 
 #endif /* ARGV_ARRAY_H */