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/* See LICENSE file for copyright and license details. */
#include "common.h"
USAGE("");
int login_shell;
int posix_mode;
void
initialise_parser_context(struct parser_context *ctx, int need_tokeniser, int need_parser)
{
memset(ctx, 0, sizeof(*ctx));
if (need_tokeniser) {
ctx->preparser_line_number = 1;
ctx->tokeniser_line_number = 1;
ctx->mode_stack = ecalloc(1, sizeof(*ctx->mode_stack));
ctx->mode_stack->she_is_comment = 1;
ctx->here_document_stack = ecalloc(1, sizeof(*ctx->here_document_stack));
ctx->here_document_stack->next = &ctx->here_document_stack->first;
}
if (need_parser) {
ctx->parser_state = ecalloc(1, sizeof(*ctx->parser_state));
}
ctx->interpreter_state = ecalloc(1, sizeof(*ctx->interpreter_state));
}
static int
is_sh(char *name)
{
if (!strcmp(name, "sh"))
return 1;
name = strrchr(name, '/');
return name && !strcmp(name, "/sh");
}
int
main(int argc, char *argv[])
{
struct parser_context ctx;
char *buffer = NULL;
size_t buffer_size = 0;
size_t buffer_head = 0;
size_t buffer_tail = 0;
ssize_t r;
size_t n, nremoved;
ARGBEGIN {
default:
usage();
} ARGEND;
if (argc)
usage();
login_shell = (argv0[0] == '-');
posix_mode = is_sh(&argv0[login_shell]);
initialise_parser_context(&ctx, 1, 1);
ctx.tty_input = (char)isatty(STDIN_FILENO);
if (ctx.tty_input)
weprintf("apsh is currently not implemented to be interactive\n");
for (;;) {
if (buffer_size - buffer_head < PARSE_RINGBUFFER_MIN_AVAILABLE) {
if (buffer_tail && buffer_head - buffer_tail <= buffer_tail) {
memcpy(&buffer[0], &buffer[buffer_tail], buffer_head - buffer_tail);
buffer_head -= buffer_tail;
buffer_tail = 0;
}
if (buffer_size - buffer_head < PARSE_RINGBUFFER_MIN_AVAILABLE)
buffer = erealloc(buffer, buffer_size += PARSE_RINGBUFFER_INCREASE_SIZE);
}
r = read(STDIN_FILENO, &buffer[buffer_head], buffer_size - buffer_head);
if (r <= 0) {
if (!r)
break;
eprintf("read <stdin>:");
}
n = (size_t)r;
buffer_head += n;
buffer_tail += n = parse(&ctx, &buffer[buffer_tail], buffer_head - buffer_tail, &nremoved);
buffer_head -= nremoved;
}
ctx.end_of_file_reached = 1;
buffer_tail += parse(&ctx, &buffer[buffer_tail], buffer_head - buffer_tail, &nremoved);
buffer_head -= nremoved;
if (buffer_tail != buffer_head || ctx.premature_end_of_file)
eprintf("premature end of file reached\n");
free(ctx.parser_state->commands);
free(ctx.parser_state->arguments);
free(ctx.parser_state->redirections);
free(ctx.parser_state);
free(ctx.here_document_stack);
free(ctx.interpreter_state);
free(buffer);
return 0;
}
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