Use libweb's form API

This functionality was moved from slcl to libweb since it can be shared
with other web applications.

1 files changed, 106 insertions, 326 deletions

diff --git a/main.c b/main.c
index 1b70542..9bf011a 100644
--- a/main.c
+++ b/main.c
@@ -12,6 +12,7 @@
 #include "hex.h"
 #include "page.h"
 #include "style.h"
+#include <libweb/form.h>
 #include <libweb/handler.h>
 #include <libweb/http.h>
 #include <libweb/wildcard_cmp.h>
@@ -36,11 +37,6 @@
 
 #define STYLE_PATH "style.css"
 
-struct form
-{
-    char *key, *value;
-};
-
 struct user_args
 {
     struct auth *a;
@@ -125,188 +121,14 @@ end:
     return ret;
 }
 
-static char *alloc_form_data(const char *const s, const char **const end)
-{
-    const char *const next = strchr(s, '&');
-    const size_t len = next ? next - s : strlen(s);
-    char *const data = malloc(len + 1);
-
-    if (!data)
-    {
-        fprintf(stderr, "%s: malloc(3): %s\n", __func__, strerror(errno));
-        return NULL;
-    }
-
-    memcpy(data, s, len);
-    data[len] = '\0';
-    *end = s + len;
-
-    if (next)
-        *end += 1;
-
-    return data;
-}
-
-static void form_free(struct form *const f)
-{
-    if (f)
-    {
-        free(f->key);
-        free(f->value);
-    }
-}
-
-static void forms_free(struct form *const f, const size_t n)
-{
-    if (f)
-        for (size_t i = 0; i < n; i++)
-            form_free(&f[i]);
-
-    free(f);
-}
-
-static int append_form(struct form **const forms, const char **const s,
-    size_t *const n)
-{
-    int ret = -1;
-    const char *end;
-    char *const data = alloc_form_data(*s, &end), *enckey = NULL,
-        *encvalue = NULL, *key = NULL, *value = NULL;
-    struct form *f = NULL, *fs = NULL;
-
-    if (!data)
-    {
-        fprintf(stderr, "%s: alloc_form_data failed\n", __func__);
-        goto end;
-    }
-
-    const char *const sep = strchr(data, '=');
-
-    if (!sep)
-    {
-        fprintf(stderr, "%s: strchr(3) returned NULL\n", __func__);
-        ret = 1;
-        goto end;
-    }
-    else if (!data || !*(sep + 1))
-    {
-        fprintf(stderr, "%s: expected key=value (%s)\n", __func__, data);
-        ret = 1;
-        goto end;
-    }
-
-    const size_t keylen = sep - data;
-
-    if (!(enckey = strndup(data, keylen)))
-    {
-        fprintf(stderr, "%s: strndup(3) enckey: %s\n",
-            __func__, strerror(errno));
-        goto end;
-    }
-    else if (!(encvalue = strdup(sep + 1)))
-    {
-        fprintf(stderr, "%s: strdup(3) encvalue: %s\n",
-            __func__, strerror(errno));
-        goto end;
-    }
-    else if (!(fs = realloc(*forms, (*n + 1) * sizeof **forms)))
-    {
-        fprintf(stderr, "%s: realloc(3): %s\n", __func__, strerror(errno));
-        goto end;
-    }
-
-    *forms = fs;
-
-    /* HTML input forms use '+' for whitespace, rather than %20. */
-    if ((ret = http_decode_url(enckey, true, &key)))
-    {
-        fprintf(stderr, "%s: http_decode_url enckey failed\n", __func__);
-        goto end;
-    }
-    else if ((ret = http_decode_url(encvalue, true, &value)))
-    {
-        fprintf(stderr, "%s: http_decode_url encvalue failed\n", __func__);
-        goto end;
-    }
-
-    f = &(*forms)[(*n)++];
-
-    *f = (const struct form)
-    {
-        .key = key,
-        .value = value
-    };
-
-    *s = end;
-    ret = 0;
-
-end:
-    if (ret)
-    {
-        free(key);
-        free(value);
-    }
-
-    free(enckey);
-    free(encvalue);
-    free(data);
-    return ret;
-}
-
-static int get_forms(const struct http_payload *const pl,
-    struct form **const forms, size_t *const outn)
-{
-    int ret = -1;
-    const struct http_post *const p = &pl->u.post;
-    struct form *f = NULL;
-
-    if (!p->data)
-    {
-        fprintf(stderr, "%s: expected non-NULL buffer\n", __func__);
-        ret = 1;
-        goto end;
-    }
-
-    const char *s = p->data;
-
-    *outn = 0;
-
-    while (*s)
-        if ((ret = append_form(&f, &s, outn)))
-        {
-            if (ret < 0)
-                fprintf(stderr, "%s: append_form failed\n", __func__);
-
-            goto end;
-        }
-
-    *forms = f;
-    ret = 0;
-
-end:
-    if (ret)
-        forms_free(f, *outn);
-
-    return ret;
-}
-
 static int check_credentials(struct auth *const a,
-    const struct form *const forms, const size_t n, char **const cookie)
+    const struct form *const forms, char **const cookie)
 {
-    const char *username = NULL, *pwd = NULL;
+    const char *const username = form_value(forms, "username"),
+        *const pwd = form_value(forms, "password");
 
     *cookie = NULL;
 
-    for (size_t i = 0; i < n; i++)
-    {
-        const struct form *const f = &forms[i];
-
-        if (!strcmp(f->key, "username"))
-            username = f->value;
-        else if (!strcmp(f->key, "password"))
-            pwd = f->value;
-    }
-
     if (!username || !pwd)
     {
         fprintf(stderr, "%s: missing credentials\n", __func__);
@@ -325,19 +147,18 @@ static int login(const struct http_payload *const pl,
     struct http_response *const r, void *const user)
 {
     int ret = -1;
-    size_t n = 0;
     struct form *forms = NULL;
     const struct user_args *const ua = user;
     char *cookie = NULL;
 
-    if ((ret = get_forms(pl, &forms, &n)))
+    if ((ret = form_alloc(pl->u.post.data, &forms)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: get_forms failed\n", __func__);
 
         goto end;
     }
-    else if ((ret = check_credentials(ua->a, forms, n, &cookie)))
+    else if ((ret = check_credentials(ua->a, forms, &cookie)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: check_credentials failed\n", __func__);
@@ -359,7 +180,7 @@ static int login(const struct http_payload *const pl,
     ret = 0;
 
 end:
-    forms_free(forms, n);
+    form_free(forms);
     free(cookie);
 
     if (ret > 0 && (ret = page_failed_login(r)))
@@ -563,7 +384,6 @@ static int check_search_input(const struct http_payload *const p,
 {
     int ret = auth_cookie(a, &p->cookie);
     struct form *forms = NULL;
-    size_t n = 0;
 
     if (ret < 0)
     {
@@ -575,7 +395,7 @@ static int check_search_input(const struct http_payload *const p,
         *f = page_forbidden;
         goto end;
     }
-    else if ((ret = get_forms(p, &forms, &n)))
+    else if ((ret = form_alloc(p->u.post.data, &forms)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: get_forms failed\n", __func__);
@@ -585,17 +405,8 @@ static int check_search_input(const struct http_payload *const p,
         goto end;
     }
 
-    const char *tdir = NULL, *tres = NULL;
-
-    for (size_t i = 0; i < n; i++)
-    {
-        const struct form *const f = &forms[i];
-
-        if (!strcmp(f->key, "dir"))
-            tdir = f->value;
-        else if (!strcmp(f->key, "name"))
-            tres = f->value;
-    }
+    const char *const tdir = form_value(forms, "dir"),
+        *const tres = form_value(forms, "name");
 
     if (!tdir)
     {
@@ -639,7 +450,7 @@ static int check_search_input(const struct http_payload *const p,
     }
 
 end:
-    forms_free(forms, n);
+    form_free(forms);
     return ret;
 }
 
@@ -858,13 +669,12 @@ static int share(const struct http_payload *const p,
 
     int ret = -1;
     struct form *forms = NULL;
-    size_t n = 0;
     char *sympath = NULL;
     struct dynstr userpath;
 
     dynstr_init(&userpath);
 
-    if ((ret = get_forms(p, &forms, &n)))
+    if ((ret = form_alloc(p->u.post.data, &forms)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: get_forms failed\n", __func__);
@@ -873,17 +683,18 @@ static int share(const struct http_payload *const p,
 
         goto end;
     }
-    else if (n != 1)
+
+    const char *const path = form_value(forms, "name"),
+        *const username = p->cookie.field;
+    struct stat sb;
+
+    if (!path)
     {
-        fprintf(stderr, "%s: expected 1 form, got %zu\n", __func__, n);
+        fprintf(stderr, "%s: missing \"name\"\n", __func__);
         ret = page_bad_request(r);
         goto end;
     }
-
-    const char *const path = forms->value, *const username = p->cookie.field;
-    struct stat sb;
-
-    if (path_invalid(path) || *path != '/')
+    else if (path_invalid(path) || *path != '/')
     {
         fprintf(stderr, "%s: invalid path %s\n", __func__, path);
         ret = page_bad_request(r);
@@ -923,7 +734,7 @@ static int share(const struct http_payload *const p,
     ret = 0;
 
 end:
-    forms_free(forms, n);
+    form_free(forms);
     free(sympath);
     dynstr_free(&userpath);
     return ret;
@@ -1681,7 +1492,6 @@ static int createdir(const struct http_payload *const p,
     const struct auth *const a = ua->a;
     struct dynstr d, userd;
     struct form *forms = NULL;
-    size_t n = 0;
     char *encurl = NULL;
 
     dynstr_init(&d);
@@ -1693,7 +1503,7 @@ static int createdir(const struct http_payload *const p,
         ret = page_forbidden(r);
         goto end;
     }
-    else if ((ret = get_forms(p, &forms, &n)))
+    else if ((ret = form_alloc(p->u.post.data, &forms)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: get_forms failed\n", __func__);
@@ -1702,30 +1512,9 @@ static int createdir(const struct http_payload *const p,
 
         goto end;
     }
-    else if (n != 2)
-    {
-        fprintf(stderr, "%s: expected 2 forms, got %zu\n", __func__, n);
-        ret = page_bad_request(r);
-        goto end;
-    }
 
-    const char *name = NULL, *dir = NULL;
-
-    for (size_t i = 0; i < n; i++)
-    {
-        const struct form *const f = &forms[i];
-
-        if (!strcmp(f->key, "name"))
-            name = f->value;
-        else if (!strcmp(f->key, "dir"))
-            dir = f->value;
-        else
-        {
-            fprintf(stderr, "%s: unexpected key %s\n", __func__, f->key);
-            ret = page_bad_request(r);
-            goto end;
-        }
-    }
+    const char *const name = form_value(forms, "name"),
+        *const dir = form_value(forms, "dir");
 
     if (!name || !dir)
     {
@@ -1811,58 +1600,69 @@ static int createdir(const struct http_payload *const p,
     ret = 0;
 
 end:
-    forms_free(forms, n);
+    form_free(forms);
     dynstr_free(&userd);
     dynstr_free(&d);
     free(encurl);
     return ret;
 }
 
-static int check_rm_input(const struct form *const forms, const size_t n,
-    struct page_rm *const rm, int (**const cb)(struct http_response *))
+static int iterate(const char *key, const char *value, void *user)
 {
-    for (size_t i = 0; i < n; i++)
+    struct page_rm *const rm = user;
+
+    if (!strcmp(key, "dir"))
+    {
+        if (!rm->dir)
+            rm->dir = value;
+        else
+        {
+            fprintf(stderr, "%s: directory defined more than once\n",
+                __func__);
+            return 1;
+        }
+    }
+    else if (!strcmp(key, "path"))
     {
-        const struct form *const f = &forms[i];
+        const char *const path = value;
 
-        if (!strcmp(f->key, "dir"))
+        if (path_isrel(path))
         {
-            if (!rm->dir)
-                rm->dir = f->value;
-            else
-            {
-                fprintf(stderr, "%s: directory defined more than once\n",
-                    __func__);
-                *cb = page_bad_request;
-                return 1;
-            }
+            fprintf(stderr, "%s: invalid path %s\n", __func__, rm->dir);
+            return 1;
         }
-        else if (!strcmp(f->key, "path"))
+
+        const char **tmp = realloc(rm->items, (rm->n + 1) * sizeof *tmp);
+
+        if (!tmp)
         {
-            const char *const path = f->value;
+            fprintf(stderr, "%s: realloc(3): %s\n",
+                __func__, strerror(errno));
+            return -1;
+        }
 
-            if (path_isrel(path))
-            {
-                fprintf(stderr, "%s: invalid path %s\n", __func__, rm->dir);
-                *cb = page_bad_request;
-                return 1;
-            }
+        tmp[rm->n++] = path;
+        rm->items = tmp;
+    }
+
+    return 0;
+}
 
-            const char **tmp = realloc(rm->items, (rm->n + 1) * sizeof *tmp);
+static int check_rm_input(const struct form *const forms,
+    struct page_rm *const rm, int (**const cb)(struct http_response *))
+{
+    const int ret = form_foreach(forms, iterate, rm);
 
-            if (!tmp)
-            {
-                fprintf(stderr, "%s: realloc(3): %s\n",
-                    __func__, strerror(errno));
-                return -1;
-            }
+    if (ret)
+    {
+        if (ret < 0)
+            fprintf(stderr, "%s: form_foreach failed\n", __func__);
+        else
+            *cb = page_bad_request;
 
-            tmp[rm->n++] = path;
-            rm->items = tmp;
-        }
+        return ret;
     }
-
-    if (!rm->dir)
+    else if (!(rm->dir = form_value(forms, "dir")))
     {
         fprintf(stderr, "%s: expected non-null dir\n", __func__);
         *cb = page_bad_request;
@@ -1885,7 +1685,6 @@ static int confirm_rm(const struct http_payload *const p,
     const struct user_args *const ua = user;
     struct form *forms = NULL;
     const char **items = NULL;
-    size_t n = 0;
     int (*f)(struct http_response *);
     struct page_rm rm = {0};
 
@@ -1895,7 +1694,7 @@ static int confirm_rm(const struct http_payload *const p,
         ret = page_forbidden(r);
         goto end;
     }
-    else if ((ret = get_forms(p, &forms, &n)))
+    else if ((ret = form_alloc(p->u.post.data, &forms)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: get_forms failed\n", __func__);
@@ -1904,7 +1703,7 @@ static int confirm_rm(const struct http_payload *const p,
 
         goto end;
     }
-    else if ((ret = check_rm_input(forms, n, &rm, &f)))
+    else if ((ret = check_rm_input(forms, &rm, &f)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: check_rm_input failed\n", __func__);
@@ -1921,38 +1720,12 @@ static int confirm_rm(const struct http_payload *const p,
     }
 
 end:
-    forms_free(forms, n);
+    form_free(forms);
     free(items);
     free(rm.items);
     return ret;
 }
 
-static const char *find_rm_dir(const struct form *const forms, const size_t n,
-    int (**const cb)(struct http_response *))
-{
-    const char *dir = NULL;
-
-    for (size_t i = 0; i < n; i++)
-    {
-        const struct form *const f = &forms[i];
-
-        if (!strcmp(f->key, "dir"))
-        {
-            if (!dir)
-                dir = f->value;
-            else
-            {
-                fprintf(stderr, "%s: directory defined more than once\n",
-                    __func__);
-                *cb = page_bad_request;
-                return NULL;
-            }
-        }
-    }
-
-    return dir;
-}
-
 static int fifo_notify_remove(int *const fd, const char *const path,
     const char *const body)
 {
@@ -2130,27 +1903,30 @@ end:
     return ret;
 }
 
-static int do_rm(struct user_args *const ua, const struct form *const forms,
-    const size_t n, const char *const dir)
+struct do_rm
+{
+    struct user_args *const ua;
+    const char *const dir;
+};
+
+static int do_rm(const char *const key, const char *const value,
+    void *const user)
 {
-    for (size_t i = 0; i < n; i++)
+    const struct do_rm *const rm = user;
+
+    if (!strcmp(key, "path"))
     {
-        const struct form *const f = &forms[i];
+        const char *const path = value;
 
-        if (!strcmp(f->key, "path"))
+        if (path_isrel(path))
         {
-            const char *const path = f->value;
-
-            if (path_isrel(path))
-            {
-                fprintf(stderr, "%s: invalid path %s\n", __func__, path);
-                return 1;
-            }
-            else if (rm_item(ua, dir, f->value))
-            {
-                fprintf(stderr, "%s: rm_item failed\n", __func__);
-                return -1;
-            }
+            fprintf(stderr, "%s: invalid path %s\n", __func__, path);
+            return 1;
+        }
+        else if (rm_item(rm->ua, rm->dir, value))
+        {
+            fprintf(stderr, "%s: rm_item failed\n", __func__);
+            return -1;
         }
     }
 
@@ -2164,7 +1940,6 @@ static int rm(const struct http_payload *const p,
     struct user_args *const ua = user;
     const struct auth *const a = ua->a;
     struct form *forms = NULL;
-    size_t n = 0;
     const struct http_cookie *const c = &p->cookie;
     const char *username = c->field, *adir;
     struct dynstr d, userdir;
@@ -2183,7 +1958,7 @@ static int rm(const struct http_payload *const p,
         fprintf(stderr, "%s: auth_dir failed\n", __func__);
         goto end;
     }
-    else if ((ret = get_forms(p, &forms, &n)))
+    else if ((ret = form_alloc(p->u.post.data, &forms)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: get_forms failed\n", __func__);
@@ -2193,13 +1968,12 @@ static int rm(const struct http_payload *const p,
         goto end;
     }
 
-    int (*f)(struct http_response *);
-    const char *const dir = find_rm_dir(forms, n, &f);
+    const char *const dir = form_value(forms, "dir");
 
     if (!dir)
     {
         fprintf(stderr, "%s: expected non-null directory\n", __func__);
-        ret = f(r);
+        ret = page_bad_request(r);
         goto end;
     }
     else if (dirname_invalid(dir))
@@ -2213,13 +1987,19 @@ static int rm(const struct http_payload *const p,
         fprintf(stderr, "%s: dynstr_append failed\n", __func__);
         goto end;
     }
-    else if ((ret = do_rm(ua, forms, n, userdir.str)))
+
+    struct do_rm args =
+    {
+        .dir = userdir.str,
+        .ua = ua
+    };
+
+    if ((ret = form_foreach(forms, do_rm, &args)))
     {
         if (ret < 0)
             fprintf(stderr, "%s: do_rm failed\n", __func__);
-        else if ((ret = f(r)))
-            fprintf(stderr, "%s: rm callback failed\n", __func__);
 
+        ret = page_bad_request(r);
         goto end;
     }
     else if (dynstr_append(&d, "/user%s", dir))
@@ -2244,7 +2024,7 @@ static int rm(const struct http_payload *const p,
 end:
     dynstr_free(&d);
     dynstr_free(&userdir);
-    forms_free(forms, n);
+    form_free(forms);
     return ret;
 }