From: Neelesh Gupta Date: Thu, 12 Sep 2013 14:26:54 +0000 (+0530) Subject: discover: Add an asynchronous version of load_url X-Git-Tag: v1.0.0~425 X-Git-Url: https://git.ozlabs.org/?p=petitboot;a=commitdiff_plain;h=ce1875fe6d550803879cad4ed168229e154c0d3c discover: Add an asynchronous version of load_url A new load_url_async() function handles retrieving the resources by forking an external process which currently blocks the parent waiting for the process to complete. This patch modifies the load_*() functions to handle it asynchronously by providing the exit callback and returning without waiting for the child process to exit. Signed-off-by: Jeremy Kerr Signed-off-by: Neelesh Gupta --- diff --git a/discover/paths.c b/discover/paths.c index ce90cae..a1f65ec 100644 --- a/discover/paths.c +++ b/discover/paths.c @@ -14,6 +14,12 @@ #define DEVICE_MOUNT_BASE (LOCAL_STATE_DIR "/petitboot/mnt") +struct load_url_async_data { + load_url_callback url_cb; + void *ctx; + int status; +}; + const char *mount_base(void) { return DEVICE_MOUNT_BASE; @@ -49,34 +55,70 @@ static char *local_name(void *ctx) return ret; } +static void load_url_exit_cb(struct process *process) +{ + struct load_url_async_data *url_data = process->data; + + pb_log("The download client '%s' [pid %d] exited, rc %d\n", + process->path, process->pid, process->exit_status); + + if (!url_data->status) + url_data->url_cb(url_data->ctx, &(url_data->status)); + + process_release(process); +} + /** * pb_load_nfs - Mounts the NFS export and returns the local file path. * * Returns the local file path in a talloc'ed character string on success, * or NULL on error. */ -static char *load_nfs(void *ctx, struct pb_url *url) +static char *load_nfs(void *ctx, struct pb_url *url, + struct load_url_async_data *url_data) { char *local, *opts; int result; + struct process *process; + const char *argv[] = { + pb_system_apps.mount, + "-t", "nfs", + NULL, + url->host, + url->dir, + NULL, + NULL, + }; local = local_name(ctx); - if (!local) return NULL; + argv[6] = local; result = pb_mkdir_recursive(local); - if (result) goto fail; opts = talloc_strdup(NULL, "ro,nolock,nodiratime"); + argv[3] = opts; if (url->port) opts = talloc_asprintf_append(opts, ",port=%s", url->port); - result = process_run_simple(ctx, pb_system_apps.mount, "-t", "nfs", - opts, url->host, url->dir, local, NULL); + if (url_data) { + process = process_create(ctx); + + process->path = pb_system_apps.mount; + process->argv = argv; + process->exit_cb = load_url_exit_cb; + process->data = url_data; + + result = process_run_async(process); + if (result) + process_release(process); + } else { + result = process_run_simple_argv(ctx, argv); + } talloc_free(opts); @@ -100,20 +142,41 @@ fail: * Returns the local file path in a talloc'ed character string on success, * or NULL on error. */ -static char *load_sftp(void *ctx, struct pb_url *url) +static char *load_sftp(void *ctx, struct pb_url *url, + struct load_url_async_data *url_data) { char *host_path, *local; int result; + struct process *process; + const char *argv[] = { + pb_system_apps.sftp, + NULL, + NULL, + NULL, + }; local = local_name(ctx); - if (!local) return NULL; + argv[2] = local; host_path = talloc_asprintf(local, "%s:%s", url->host, url->path); + argv[1] = host_path; + + if (url_data) { + process = process_create(ctx); - result = process_run_simple(ctx, pb_system_apps.sftp, host_path, - local, NULL); + process->path = pb_system_apps.sftp; + process->argv = argv; + process->exit_cb = load_url_exit_cb; + process->data = url_data; + + result = process_run_async(process); + if (result) + process_release(process); + } else { + result = process_run_simple_argv(ctx, argv); + } if (result) goto fail; @@ -132,12 +195,14 @@ fail: * or NULL on error. */ -static char *load_tftp(void *ctx, struct pb_url *url) +static char *load_tftp(void *ctx, struct pb_url *url, + struct load_url_async_data *url_data) { int result; const char *argv[10]; const char **p; char *local; + struct process *process; local = local_name(ctx); @@ -158,13 +223,23 @@ static char *load_tftp(void *ctx, struct pb_url *url) *p++ = url->port; /* 8 */ *p++ = NULL; /* 9 */ - result = process_run_simple_argv(ctx, argv); + if (url_data) { + process = process_create(ctx); + + process->path = pb_system_apps.tftp; + process->argv = argv; + process->exit_cb = load_url_exit_cb; + process->data = url_data; + + result = process_run_async(process); + } else { + result = process_run_simple_argv(ctx, argv); + } if (!result) return local; /* next try tftp-hpa args */ - p = argv; *p++ = pb_system_apps.tftp; /* 1 */ *p++ = "-m"; /* 2 */ @@ -178,7 +253,14 @@ static char *load_tftp(void *ctx, struct pb_url *url) *p++ = local; /* 9 */ *p++ = NULL; /* 10 */ - result = process_run_simple_argv(ctx, argv); + if (url_data) { + process->argv = argv; + result = process_run_async(process); + if (result) + process_release(process); + } else { + result = process_run_simple_argv(ctx, argv); + } if (!result) return local; @@ -199,12 +281,14 @@ enum wget_flags { * or NULL on error. */ -static char *load_wget(void *ctx, struct pb_url *url, enum wget_flags flags) +static char *load_wget(void *ctx, struct pb_url *url, enum wget_flags flags, + struct load_url_async_data *url_data) { int result; const char *argv[7]; const char **p; char *local; + struct process *process; local = local_name(ctx); @@ -223,7 +307,20 @@ static char *load_wget(void *ctx, struct pb_url *url, enum wget_flags flags) *p++ = "--no-check-certificate"; /* 6 */ *p++ = NULL; /* 7 */ - result = process_run_simple_argv(ctx, argv); + if (url_data) { + process = process_create(ctx); + + process->path = pb_system_apps.wget; + process->argv = argv; + process->exit_cb = load_url_exit_cb; + process->data = url_data; + + result = process_run_async(process); + if (result) + process_release(process); + } else { + result = process_run_simple_argv(ctx, argv); + } if (result) goto fail; @@ -239,42 +336,56 @@ fail: * load_url - Loads a (possibly) remote URL and returns the local file * path. * @ctx: The talloc context to associate with the returned string. - * @URL: The remote file URL. + * @url: The remote file URL. * @tempfile: An optional variable pointer to be set when a temporary local * file is created. + * @url_cb: An optional callback pointer if the caller wants to load url + * asynchronously. * * Returns the local file path in a talloc'ed character string on success, * or NULL on error. */ -char *load_url(void *ctx, struct pb_url *url, unsigned int *tempfile) +char *load_url_async(void *ctx, struct pb_url *url, unsigned int *tempfile, + load_url_callback url_cb) { char *local; int tmp = 0; + struct load_url_async_data *url_data; if (!url) return NULL; + url_data = NULL; + + if (url_cb) { + url_data = talloc_zero(ctx, struct load_url_async_data); + url_data->url_cb = url_cb; + url_data->ctx = ctx; + url_data->status = 0; + } + switch (url->scheme) { case pb_url_ftp: case pb_url_http: - local = load_wget(ctx, url, 0); + local = load_wget(ctx, url, 0, url_data); tmp = !!local; break; case pb_url_https: - local = load_wget(ctx, url, wget_no_check_certificate); + local = load_wget(ctx, url, wget_no_check_certificate, + url_data); tmp = !!local; break; case pb_url_nfs: - local = load_nfs(ctx, url); + local = load_nfs(ctx, url, url_data); tmp = !!local; break; case pb_url_sftp: - local = load_sftp(ctx, url); + local = load_sftp(ctx, url, url_data); tmp = !!local; break; case pb_url_tftp: - local = load_tftp(ctx, url); + local = load_tftp(ctx, url, url_data); tmp = !!local; break; default: @@ -288,3 +399,8 @@ char *load_url(void *ctx, struct pb_url *url, unsigned int *tempfile) return local; } + +char *load_url(void *ctx, struct pb_url *url, unsigned int *tempfile) +{ + return load_url_async(ctx, url, tempfile, NULL); +} diff --git a/discover/paths.h b/discover/paths.h index 20a2249..93788e9 100644 --- a/discover/paths.h +++ b/discover/paths.h @@ -16,7 +16,12 @@ char *join_paths(void *alloc_ctx, const char *a, const char *b); */ const char *mount_base(void); +typedef void (*load_url_callback)(void *data, int *status); + /* Load a (potentially remote) file, and return a guaranteed-local name */ +char *load_url_async(void *ctx, struct pb_url *url, unsigned int *tempfile, + load_url_callback url_cb); + char *load_url(void *ctx, struct pb_url *url, unsigned int *tempfile); #endif /* PATHS_H */