diff options
| author |  Adam Chlipala <adamc@hcoop.net> | 2008-07-29 15:25:42 -0400 |
|---|---|---|
| committer | Adam Chlipala <adamc@hcoop.net> | 2008-07-29 15:25:42 -0400 |
| commit | cb3b3831a07d6674a5fa02e3e8a1e4329b58cb34 (patch) | |
| tree | 7b6064344549091735d28d42ac9fb19073e9760a /src/c | |
| parent | 6855e4766fa8d07e2f3e3cd468de6c58fed0c903 (diff) | |
Unurlifying a datatype; longjmp-based error signaling mechanism
Diffstat (limited to 'src/c')
| -rw-r--r-- | src/c/driver.c | 62 | ||||
| -rw-r--r-- | src/c/lacweb.c | 51 |
2 files changed, 105 insertions, 8 deletions
diff --git a/src/c/driver.c b/src/c/driver.c index 90538104..21001d0c 100644 --- a/src/c/driver.c +++ b/src/c/driver.c @@ -13,8 +13,6 @@ int lw_port = 8080; int lw_backlog = 10; int lw_bufsize = 1024; -void lw_handle(lw_context, char*); - typedef struct node { int fd; struct node *next; @@ -51,6 +49,8 @@ static int dequeue() { static pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER; static pthread_cond_t queue_cond = PTHREAD_COND_INITIALIZER; +#define MAX_RETRIES 5 + static void *worker(void *data) { int me = *(int *)data; lw_context ctx = lw_init(1024, 1024); @@ -68,6 +68,7 @@ static void *worker(void *data) { printf("Handling connection with thread #%d.\n", me); while (1) { + unsigned retries_left = MAX_RETRIES; int r = recv(sock, back, lw_bufsize - (back - buf), 0); if (r < 0) { @@ -138,11 +139,58 @@ static void *worker(void *data) { printf("Serving URI %s....\n", path); - lw_write (ctx, "HTTP/1.1 200 OK\r\n"); - lw_write(ctx, "Content-type: text/html\r\n\r\n"); - lw_write(ctx, "<html>"); - lw_handle(ctx, path); - lw_write(ctx, "</html>"); + while (1) { + failure_kind fk; + + lw_write(ctx, "HTTP/1.1 200 OK\r\n"); + lw_write(ctx, "Content-type: text/html\r\n\r\n"); + lw_write(ctx, "<html>"); + + fk = lw_begin(ctx, path); + if (fk == SUCCESS) { + lw_write(ctx, "</html>"); + break; + } else if (fk == BOUNDED_RETRY) { + if (retries_left) { + printf("Error triggers bounded retry: %s\n", lw_error_message(ctx)); + --retries_left; + } + else { + printf("Fatal error (out of retries): %s\n", lw_error_message(ctx)); + + lw_reset_keep_error_message(ctx); + lw_write(ctx, "HTTP/1.1 500 Internal Server Error\n\r"); + lw_write(ctx, "Content-type: text/plain\r\n\r\n"); + lw_write(ctx, "Fatal error (out of retries): "); + lw_write(ctx, lw_error_message(ctx)); + lw_write(ctx, "\n"); + } + } else if (fk == UNLIMITED_RETRY) + printf("Error triggers unlimited retry: %s\n", lw_error_message(ctx)); + else if (fk == FATAL) { + printf("Fatal error: %s\n", lw_error_message(ctx)); + + lw_reset_keep_error_message(ctx); + lw_write(ctx, "HTTP/1.1 500 Internal Server Error\n\r"); + lw_write(ctx, "Content-type: text/plain\r\n\r\n"); + lw_write(ctx, "Fatal error: "); + lw_write(ctx, lw_error_message(ctx)); + lw_write(ctx, "\n"); + + break; + } else { + printf("Unknown lw_handle return code!\n"); + + lw_reset_keep_request(ctx); + lw_write(ctx, "HTTP/1.1 500 Internal Server Error\n\r"); + lw_write(ctx, "Content-type: text/plain\r\n\r\n"); + lw_write(ctx, "Unknown lw_handle return code!\n"); + + break; + } + + lw_reset_keep_request(ctx); + } lw_send(ctx, sock); diff --git a/src/c/lacweb.c b/src/c/lacweb.c index 9543c642..523071fd 100644 --- a/src/c/lacweb.c +++ b/src/c/lacweb.c @@ -3,15 +3,24 @@ #include <string.h> #include <ctype.h> #include <assert.h> +#include <setjmp.h> +#include <stdarg.h> #include "types.h" lw_unit lw_unit_v = {}; +#define ERROR_BUF_LEN 1024 + struct lw_context { char *page, *page_front, *page_back; char *heap, *heap_front, *heap_back; char **inputs; + + jmp_buf jmp_buf; + + failure_kind failure_kind; + char error_message[ERROR_BUF_LEN]; }; extern int lw_inputs_len; @@ -27,6 +36,9 @@ lw_context lw_init(size_t page_len, size_t heap_len) { ctx->inputs = calloc(lw_inputs_len, sizeof(char *)); + ctx->failure_kind = SUCCESS; + ctx->error_message[0] = 0; + return ctx; } @@ -37,12 +49,49 @@ void lw_free(lw_context ctx) { free(ctx); } -void lw_reset(lw_context ctx) { +void lw_reset_keep_request(lw_context ctx) { + ctx->page_front = ctx->page; + ctx->heap_front = ctx->heap; + + ctx->failure_kind = SUCCESS; + ctx->error_message[0] = 0; +} + +void lw_reset_keep_error_message(lw_context ctx) { ctx->page_front = ctx->page; ctx->heap_front = ctx->heap; + + ctx->failure_kind = SUCCESS; +} + +void lw_reset(lw_context ctx) { + lw_reset_keep_request(ctx); memset(ctx->inputs, 0, lw_inputs_len * sizeof(char *)); } +void lw_handle(lw_context, char *); + +failure_kind lw_begin(lw_context ctx, char *path) { + if (!setjmp(ctx->jmp_buf)) + lw_handle(ctx, path); + + return ctx->failure_kind; +} + +void lw_error(lw_context ctx, failure_kind fk, const char *fmt, ...) { + va_list ap; + va_start(ap, fmt); + + ctx->failure_kind = fk; + vsnprintf(ctx->error_message, ERROR_BUF_LEN, fmt, ap); + + longjmp(ctx->jmp_buf, 1); +} + +char *lw_error_message(lw_context ctx) { + return ctx->error_message; +} + int lw_input_num(char*); void lw_set_input(lw_context ctx, char *name, char *value) { |